Odd html/js button display glitch

The eyewear company I work for has been developing a custom system for processing eyeglass lens orders through our lab.


In our labs, we are using iPads to display the different 'stations' the jobs are currently at.


When staff finish at one station, and move to the next station, they have a button for the new station, which they select on that job.


We've been having an ongoing, intermittent issue, with the displayed buttons, 'glitching' out, where the buttons are no longer displayed correctly.


This occurs in both mobile Safari and Chrome.


We were originally using Chrome webkit on this page, and our devs switched to Safari webkit, to see if that made a difference, but we have yet to be able to squash, or even narrow down 'why' this particular display bug happens.


Has anyone seen any issue like this before, and if so, any ideas on how to remedy it?


https://imgur.com/o3jPLl9

https://imgur.com/BECt8S2

https://imgur.com/AtXHRfh