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Having now read all the logs on this topic I really hope that Garmin make the change to the Firmware feature that will allow us "the users" to decide if we want a 2, 3 or 4 digit display on coordinates. It does not make sense for Geocaching.com to use one format and Garmin (one of the largest suppliers to us Geocachers) to decide otherwise.

 

So come on Garmin get your act together please, just for once!!

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14 minutes ago, wendykmj said:

Having now read all the logs on this topic I really hope that Garmin make the change to the Firmware feature that will allow us "the users" to decide if we want a 2, 3 or 4 digit display on coordinates. It does not make sense for Geocaching.com to use one format and Garmin (one of the largest suppliers to us Geocachers) to decide otherwise.

 

So come on Garmin get your act together please, just for once!!

First, Garmin and Geocaching.com are not the same thing. Occasionally, the companies work together to make their products interact nicely. But they are two independent companies that make decisions about their products independently. You can't fault Garmin for this.

Second, I'm not sure how an extra decimal place really affects anything. You can just ignore that 4th decimal and be on your merry way. By the way, just for comparison, 1 minute of latitude covers about 6068 feet in distance. That means 0.001 minutes covers about 6 feet, and that extra decimal space that Garmin is now introducing, 0.0001 minutes covers 0.6 feet, or about 7.2 inches. Your handheld from Garmin isn't really precise enough to guarantee that your reading down to 3 decimal places is spot on, let alone 4 decimal places, but it is good enough to guarantee precision beyond the 60 feet that  So yes, Garmin really shouldn't be displaying that last decimal place as that number isn't accurate. But it is easy enough to ignore. But really, for geocaching, there's no need to even look at the coordinates of your device in real time. Just look at the distance to the cache and watch it count down. When you're within 30 feet, read the description again and put the GPS down, because your eyes and your brain will do more for you than your GPS at that point.

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27 minutes ago, wendykmj said:

Having now read all the logs on this topic I really hope that Garmin make the change to the Firmware feature that will allow us "the users" to decide if we want a 2, 3 or 4 digit display on coordinates. It does not make sense for Geocaching.com to use one format and Garmin (one of the largest suppliers to us Geocachers) to decide otherwise.

 

So come on Garmin get your act together please, just for once!!

 

So you think Groundspeak sets the standard for GPS coordinates?

 

That's rich.

 

Maybe Groundspeak should 'get thier act together' and start including the additional digit in thier posted coordinates...

 

Or...

 

You can simply ignore the extra digit, or even use a different coordinate system all together... 

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3 minutes ago, Mineral2 said:

But really, for geocaching, there's no need to even look at the coordinates of your device in real time. Just look at the distance to the cache and watch it count down. When you're within 30 feet, read the description again and put the GPS down, because your eyes and your brain will do more for you than your GPS at that point.

 

Exactly!

 

 

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12 hours ago, Mineral2 said:

First, Garmin and Geocaching.com are not the same thing. Occasionally, the companies work together to make their products interact nicely. But they are two independent companies that make decisions about their products independently. You can't fault Garmin for this.

I'm not sure wendykmj was faulting garmin so much as suggesting they let people that using geocaching.com set the unit to follow the same standard. It's like complaining if garmin only supported decimal degrees and not the decimal minues geocaching.com presents.

 

12 hours ago, Mineral2 said:

Second, I'm not sure how an extra decimal place really affects anything. You can just ignore that 4th decimal and be on your merry way. By the way, just for comparison, 1 minute of latitude covers about 6068 feet in distance. That means 0.001 minutes covers about 6 feet, and that extra decimal space that Garmin is now introducing, 0.0001 minutes covers 0.6 feet, or about 7.2 inches.

That's a good argument for not displaying the 4th decimal place, isn't it? Anyway, I basically agree that it's not a big deal, but it does annoy me when I go to enter coordinates when the 66st defaults to the current location, thus putting in a random number in the 4th decimal place that I have to zero if I want to put the precise coordinates I got from solving the puzzle or whatever. It doesn't really matter, but it would be convenient if I could configure the 66st to not bother with the 4th decimal place since, as you point out, it's pointless.

 

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Posted (edited)

Engineers understand that the last digit (and only the last digit) in a measurement is an estimate. By writing 25.45 cm, you indicate that you are sure that the measurement was between 25.4 cm and 25.5 cm, and you estimate that it was about 5/10 of the way between them. Therefore coordinates should be written to four decimal places to indicate you are sure the measurement is correct to three decimal places and the fourth decimal place is only a guess or only three significant figures.

Edited by Capt. Bob
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3 hours ago, Capt. Bob said:

Engineers understand that the last digit (and only the last digit) in a measurement is an estimate. By writing 25.45 cm, you indicate that you are sure that the measurement was between 25.4 cm and 25.5 cm, and you estimate that it was about 5/10 of the way between them. Therefore coordinates should be written to four decimal places to indicate you are sure the measurement is correct to three decimal places and the fourth decimal place is only a guess or only three significant figures.

Well, first of all, engineers might understand that, but users use the interface, so what they understand is more important.

 

But is your statement correct? My experience with engineers is that they will assume that if you write 25.45 cm, you're implying you have that level of accuracy, so they'd expect the true value to be between 25.445 and 25.455. I've never heard of this "the last digit is always BS" rule before.

 

Anyway, even if we're not worried about a geocacher that doesn't understand why the format is different than they're seeing everywhere else, that explains displaying the 4th digit, but as I pointed out, it doesn't explain requiring the 4th digit as input.

 

Again, I'm not really arguing that this is a problem, I'm just not finding these arguments convincing. I'm satisfied with the simple argument that the hardware provides 4 digits, so they're using them all. (*yawn*)

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Posted (edited)

LOL

 

My Ferrari F80 can do >200mph, but mostly I only drive it below 100mph, so why do they insist on the Speedometer showing 225mph? It confuses me, and I demand they build the speedometer to only show 100mph as the top speed as that is all most users will need......

 

 

Edited by Atlas Cached

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2 hours ago, Atlas Cached said:

LOL

 

My Ferrari F80 can do >200mph, but mostly I only drive it below 100mph, so why do they insist on the Speedometer showing 225mph? It confuses me, and I demand they build the speedometer to only show 100mph as the top speed as that is all most users will need......

Well, no, it's more like a car that's lucky to make it to 70mph having a speedometer that goes to 225mph, right? The 4th digit makes the device look more accurate than it really is. Now if you had paid for a GPSr that really was accurate to 4 decimal places, then, like the car company, the GPSr manufacturer would be silly not to present all the accuracy you paid for so you can show it off to people even though you're using it to look for caches with coordinates that are more than an order of magnitude less accurate. But everyone here agrees that's not the case with the handheld Garmins.

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The whole point of my original comment was that the Garmin Oregon 750 offers a facility in the settings to "choose" between 2,3 or 4 digits........ but this "feature" just does not work since the latest Firmware was released. Thus the user cannot set their preference for the coordinate display. Thus Garmin are the only ones who can fix this issue by amending the Firmware.

 

From the responses it does look like many are not actually Geocachers but ""experts" in the field of coordinates and their usage and consequently don't fully understand how us Geocachers generally use our GPS devices in the field.

 

Just stating that we should ignore the 4th digit on say the Oregon 750 but on the Oregon 650 and earlier devices its only 3 digits causes lots of confusion as a number of comments have stated.

 

 

 

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42 minutes ago, wendykmj said:

From the responses it does look like many are not actually Geocachers but ""experts" in the field of coordinates and their usage and consequently don't fully understand how us Geocachers generally use our GPS devices in the field.

 

Most of us here are only here because we are geocachers..... and we 'get' what it takes to geocache. As others have stated, once you are within 30 feet of GZ, it is time to put the GPSr down and start using that fancy computer between your ears!

 

Just stating that we should ignore the 4th digit on say the Oregon 750 but on the Oregon 650 and earlier devices its only 3 digits causes lots of confusion as a number of comments have stated.

 

I just can't imagine what could possibly be so 'confusing' about ignoring any additional digits beyond the third after the decimal point. Pretty simple.

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1 hour ago, Atlas Cached said:

I just can't imagine what could possibly be so 'confusing' about ignoring any additional digits beyond the third after the decimal point. Pretty simple. 

N 37 46.5190, W 122 25.1770 or N 37 46.0519, W 122 25.0177?

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3 hours ago, dprovan said:

N 37 46.5190, W 122 25.1770 or N 37 46.0519, W 122 25.0177?

 

That's silly. We're talking about the 4th digit after the decimal, not the three digits preceding (and I think you know that).

 

An honest question would be:

 

"N 37 46.5190, W 122 25.1770 or N 37 46.519, W 122 25.177?"

 

Both coordinates are the same with or without the 4th digit.

 

Why post a dishonest argument?

 

 

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10 minutes ago, Atlas Cached said:

That's silly. We're talking about the 4th digit after the decimal, not the three digits preceding (and I think you know that).

Of course we know that. You said you couldn't imagine how it could be confusing, so I cited a common mistake people that aren't as technical as we are make with decimals. And that's even without considering that the syntax is complicated enough that those periods might not even recognized as decimal points.

 

15 minutes ago, Atlas Cached said:

Why post a dishonest argument?

There's no reason at all to post a dishonest argument, of course, so maybe next time you might try a little harder to consider how it could actually be a legitimate point made in good faith and, as in this case, not even an argument to begin with.

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Posted (edited)
30 minutes ago, dprovan said:

Of course we know that. You said you couldn't imagine how it could be confusing, so I cited a common mistake people that aren't as technical as we are make with decimals. And that's even without considering that the syntax is complicated enough that those periods might not even recognized as decimal points.

 

I just don't see how in the world having one more digit at the very end of the coordinate translates into someone somehow transposing that digit into the middle of that set of coordinates.

 

Nor can I make any honest connection between that one additional digit at the very end of the coordinates and a user somehow not recognizing the decimal points in the coordinates.

 

(in my best Joe Pesci voice) Are we to believe that for some reason, GPSr users can handle two 8 digit numbers with decimals just fine, but by adding just a single digit at the end of each (so two 9 digit numbers) somehow results in a mass hysteria causing the user to randomly place the extra trailing digit somewhere into the middle of each number sequence while simultaneously loosing all comprehension of the two decimals points in the coordinate display?

 

Wow. I mean, if this is true, maybe GPSr are not for you. Or, maybe think about using a different, less confusing coordinate system. There are so many to choose from. UTM is pretty simple....

 

 

Edited by Atlas Cached
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On 5/30/2019 at 12:58 PM, Mineral2 said:

Second, I'm not sure how an extra decimal place really affects anything. You can just ignore that 4th decimal and be on your merry way. By the way, just for comparison, 1 minute of latitude covers about 6068 feet in distance. That means 0.001 minutes covers about 6 feet, and that extra decimal space that Garmin is now introducing, 0.0001 minutes covers 0.6 feet, or about 7.2 inches. Your handheld from Garmin isn't really precise enough to guarantee that your reading down to 3 decimal places is spot on, let alone 4 decimal places.  So yes, Garmin really shouldn't be displaying that last decimal place as that number isn't accurate.

 

So this got me thinking today....

 

If, as you say, the 'extra' digit displayed in the fourth position after the decimal point can not be accurately or precisely computed by the Garmin GPSr, where then do you suppose that number is coming from? Are they using a random number generator to fill the position? Because, that is the only other option. Either the GPSr can calculate a solution for that position, or it is using a random number instead. Which do you think it really is?

 

BTW, I genuinely do not know the answer to this question. It just occurred to me that if the GPSr is actually incapable of calculating to this precision, then it must be using a random number, which just seems silly to me.

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4 hours ago, Atlas Cached said:

I just don't see how in the world having one more digit at the very end of the coordinate translates into someone somehow transposing that digit into the middle of that set of coordinates. 

When they're looking at coordinates on geocaching.com and have to enter them into the 4 digit field. Some will just be copying the number without years and years of experience with multiple formats of coordinates, and they'll be faced with copying a 3 digit number into a 4 digit field. If they have no idea what all those numbers mean and, furthermore, don't care, they'll have to guess at whether the 3 digits they have should be copied into the 4 places for digits the GPSr presents them aligned to the right or aligned to the left.

 

As I said, I'm just giving you something to imagine since you couldn't think of any confusion. I'm not claiming this is the end of the world. As I've been saying all along, 4 digits aren't a big deal.

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4 hours ago, Atlas Cached said:

If, as you say, the 'extra' digit displayed in the fourth position after the decimal point can not be accurately or precisely computed by the Garmin GPSr, where then do you suppose that number is coming from? Are they using a random number generator to fill the position? Because, that is the only other option. Either the GPSr can calculate a solution for that position, or it is using a random number instead. Which do you think it really is?

I'm no expert, but I think it's obvious that the fourth digit is accurately reflecting what the unit thinks is its location. The problem is that where it thinks it is is not typically where it actually is because of known inaccuracies in the measurements.

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10 hours ago, Atlas Cached said:

I just can't imagine what could possibly be so 'confusing' about ignoring any additional digits beyond the third after the decimal point. Pretty simple.

 

Take a quick look at these coordinates I captured on my Oregon 700 a few months back.

 

image.png.e38429910cf9323399d2d0e7de61eb01.png

 

At first glance, and I emphasis at first glance, might you read the decimal minutes as 276 and 144? Do you think that error is possible when copying the coordinates from the device onto a cache page? What used to be a straightforward task of copying digits now requires additional thought to avoid making that mistake. It's pretty simple, yes, but it's still error-prone for no improvement in accuracy.

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5 hours ago, Atlas Cached said:

If, as you say, the 'extra' digit displayed in the fourth position after the decimal point can not be accurately or precisely computed by the Garmin GPSr, where then do you suppose that number is coming from? Are they using a random number generator to fill the position? Because, that is the only other option. Either the GPSr can calculate a solution for that position, or it is using a random number instead. Which do you think it really is?

 

The fourth digit isn't from a random number generator but it might as well be as it's just reflecting what is effectively system noise. By way of experiment, I took my Oregon 700 down to the beach, where it had essentially an unobstructed view of the sky, and recorded the decimal part of the minutes of latitude over about half an hour. These are the results:

 

6590, 6594, 6593, 6597, 6597, 6599, 6599, 6597, 6595, 6592, 6593, 6590, 6592, 6593, 6593, 6593, 6592, 6592, 6593, 6595, 6595, 6595, 6592, 6591, 6590

 

For that fourth digit, what is the correct value? Pick a number, any number, and at some point you'll be right. They're varying slowly but they're essentially random, and I'm sure if I went back down there tomorrow morning with a different constellation of satellites visible I'd get a difference of at least one or two in the third decimal place, rendering anything in the fourth decimal place utterly meaningless.

Edited by barefootjeff
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3 hours ago, barefootjeff said:

 

The fourth digit isn't from a random number generator but it might as well be as it's just reflecting what is effectively system noise. By way of experiment, I took my Oregon 700 down to the beach, where it had essentially an unobstructed view of the sky, and recorded the decimal part of the minutes of latitude over about half an hour. These are the results:

 

6590, 6594, 6593, 6597, 6597, 6599, 6599, 6597, 6595, 6592, 6593, 6590, 6592, 6593, 6593, 6593, 6592, 6592, 6593, 6595, 6595, 6595, 6592, 6591, 6590

 

For that fourth digit, what is the correct value? Pick a number, any number, and at some point you'll be right. They're varying slowly but they're essentially random, and I'm sure if I went back down there tomorrow morning with a different constellation of satellites visible I'd get a difference of at least one or two in the third decimal place, rendering anything in the fourth decimal place utterly meaningless.

 

What your four decimal digit GPSr is telling you is that its level of precision is limited to three decimal places.  The fourth decimal place is a guess, or in your case, perhaps random noise.  However, you are assured the number 659 is an accurate number.

 

Suppose your GPSr only displayed three digits.  If the fourth decimal place (now hidden from view) is below five the display will be 659 but if the fourth decimal place is above five it will display 660 due to a rounding error.  What if the unit does not round up?  Then if the fourth decimal happens to vary between 5 and 9 the unit will only display 659 and not 660 which would be closer to the actual location.

 

The fourth decimal place is telling you the precision level of your GPSr and it’s up to the user to decide the final number.  However, commercial grade GPSr makes it simpler for the average user by dumbing down the display to only three decimal places.

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Posted (edited)
47 minutes ago, Capt. Bob said:

However, you are assured the number 659 is an accurate number.

 

No, I'm not assured 659 is an accurate number. Tomorrow morning, if I go back down to the beach and put my GPSr in exactly the same place (which is easy to do, because it was right on the end of a wooden bench set into the sand), chances are those first three decimal places won't be 659 but perhaps 658 or 660, or 657 or 661 or even further off than that. Garmin defines their EPE as a 50 percent confidence radius, and the very best a consumer grade GPSr can achieve is an EPE of 3 metres, so even then, 50 percent of the time the location will be more than 3 metres out. One digit in the third decimal place for latitude is about 1.8 metres, so a spread like that, 657 to 661 in my example, is going to happen even under ideal conditions. The fourth decimal place is completely meaningless in this context.

 

Oh, and by the way, when Garmin was only displaying three decimal places in the minutes, it was rounding to nearest, not truncating. How do I know? That screen shot I posted earlier, where the decimal minutes appeared as 0276 and 0144, was from coordinates I captured before the firmware update, and back then it displayed them as 028 and 014 which is what I put as GZ on my cache page. It was only after the firmware update that the 028 changed to 0276. Internally it no doubt works with even higher numerical precision and rounds to nearest when displaying the results, because that's the proper engineering thing to do, but that's done purely to avoid intermediate rounding errors from accumulating and becoming excessive. The final result doesn't need to, and in fact shouldn't, be displayed at that precision because the least significant digits in the result don't carry any useful information.

 

Edit to add: the state government's high-resolution satellite image clearly shows the bench on the beach where I had my GPSr sitting:

 

image.png.37016a8f27afbc6544e9a86db3d66c9a.png

 

It gives the latitude of the red flag as -33.52767 in decimal degrees, which is S 33 31.6602 in dd mm.mmmm format, so, assuming their imagery accuracy is better than a consumer-grade GPSr, all my readings this afternoon were a little on the low side. Perhaps tomorrow morning they'll all be a little on the high side. I guess I'll find out.

 

Edited by barefootjeff
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Of course you may have a different reading at different times.  There are a myriad of reasons for variations in readings.  Garbage in equal garbage out.  However each reading it takes at that specific moment has a precision level displayed by the fourth digit even if the data it receives is bad data.  So  garbage in equal very precise garbage out.

 

The final (fourth) digit does carry useful information.  It tells you the certainty of the third digit.  Suppose you have a three digit display and the third digit varies.   Example: 659, 658, 657, 659...etc.  Now what is your confidence level?   You should feel the '65' portion is accurate but unsure about the final digit.  The same thing applies to a four digit display. 

 

 

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3 minutes ago, Capt. Bob said:

The final (fourth) digit does carry useful information.  It tells you the certainty of the third digit.  Suppose you have a three digit display and the third digit varies.   Example: 659, 658, 657, 659...etc.  Now what is your confidence level?   You should feel the '65' portion is accurate but unsure about the final digit.  The same thing applies to a four digit display. 

 

No, no, no, a thousand times no! The accuracy of the device, to a confidence level of 50 percent, is plus or minus three metres, that's the specification the manufacturer gives, which equates to plus or minus 0.0017 minutes under ideal conditions. Don't make the mistake of confusing precision with accuracy. Just because the third decimal digit didn't change over the course of half an hour doesn't make it accurate, it just means I picked a time when it ranged from 6590 to 6599 which is a much smaller range than the specified accuracy. If the absolute correct value is 6600, I'd expect it to be within the range 6583 to 6617 for 50 percent of the time, and outside that range for the other 50 percent. That's assuming observations are taken over many days to allow for a broad range of satellite constellations. Rounding to the nearest three decimal places gives a range of 658 to 662 which is enough to tell me the sort of confidence to expect in my readings. The fourth decimal place doesn't improve that confidence.

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You forget Galileo, which is accurate up to 1 meter. Then the fourth digit makes sense.

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51 minutes ago, StefandD said:

You forget Galileo, which is accurate up to 1 meter. Then the fourth digit makes sense.

 

BINGO!

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I'm suspicious of that claim. Or cautiously optimistic.

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5 hours ago, Capt. Bob said:

What if the unit does not round up?  Then if the fourth decimal happens to vary between 5 and 9 the unit will only display 659 and not 660 which would be closer to the actual location.

If the unit didn't round up, that would be a bug.

 

Seriously, all your discussion and examples boils down to the fact that someone that understands what the 4th digit means can use that to deduce how the software, if it were there, should round the number to the nearest thousands place. That's an argument for having the software do it.

 

3 hours ago, StefandD said:

You forget Galileo, which is accurate up to 1 meter. Then the fourth digit makes sense.

As I see it, the point here isn't the accuracy of the device, it's the accuracy of geocaching.com. Even if that 4th digit were accurate on the device, it would still be a mismatch with the accuracy of the data being copied to the device from geocaching.com.

 

Having said that, the possibility of the 4th being meaningful is a concrete reason for what was originally suggested: a way to configure whether the 4th digit is displayed. The proposal was never to just get rid of it for everyone. And to me, that's kinda the clincher: the 4th digit is never really a big deal, so even while we can imagine reasons someone might not want to see it, it wouldn't be worth the time and effort to implement and document the configuration process.

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6 hours ago, Atlas Cached said:
7 hours ago, StefandD said:

You forget Galileo, which is accurate up to 1 meter. Then the fourth digit makes sense.

 

BINGO!

 

I'm pretty sure the Oregon 700 doesn't support Galileo.

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18 minutes ago, barefootjeff said:

 

I'm pretty sure the Oregon 700 doesn't support Galileo.

 

Maybe not YET. As far as I know (read it somewhere, don’t remember where), the 700 chipset supports Galileo, but it’s not „unlocked“. Maybe one of the next updates will.

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2 hours ago, Henne1312 said:

 

Maybe not YET. As far as I know (read it somewhere, don’t remember where), the 700 chipset supports Galileo, but it’s not „unlocked“. Maybe one of the next updates will.

 

Also correct.

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