Thank you Dravvy!
Your reply wasn't the specific answer to my issue but it put me on the right track. I searched the included scripts and business rules on the INC tickets and found several System Client Scripts that had the exact error scripted into them;
catch(e) {
g_form.addErrorMessage('My time entry field encountered the following error: ' + e + '.\nPlease contact support.');
I believe the issue is that the none in
inputControlsEl[0].style.display = 'none';
is in single, not double quotes, but it's another team's script, so I passed it to them to fix.
Thank you for putting me on the track to finding the issue!
