EDIT: Cooper Wheels does not seem to show this issue. ~Thanks to Tisquares
EDIT 2: Using Silver Wheels, and not having this issue.
EDIT 3: I have recreated while using Silver Wheels as well, so probably not wheel related. The issue got recreated when going to Spooky Spires specifically. I was only going to Lagoon for testing/Mining Mayhem event.
Did further testing:
No wheel- No issue in either sites
Copper Wheels- No issues.
Iron Wheels- Lucid Lagoon yes, Spooky Spires yes
Silver Wheels- Lucid Lagoon no, Spooky Spires yes
I haven't unlocked any other mine sites or wheels so can't test in others.
Something I recently noticed while mining is that the depth will suddenly be given an additional 4 counter to it.
When at the Furnace it shows 0ft and then -4ft when clicking to go to a location. Similarly, when clicking to go back to the Furnace the depth is given a +4 (ex. initial 300ft changes to 304ft).
I am currently using the Iron Wheels, so will test if it might be tied to that.
I recorded examples of both instances shown below:
-4ft example:
304ft example:
Happens on both mobile and PC for me.
Mobile: Latest Google Chrome app on Android 10
PC: Chrome Version 109.0.5414.120 on Windows 7