Hello,
My lab offers workshops and we recently updated to 10.8 an error that never really happened to me is the select by location interface loading with no layers despite layers being within the document. A few of the students and I have been having issues with it. the solution requires a reboot of ArcMap before the layers will load again. I didn't know if this issue was a bug with 10.8 - as I used 10.2, 10.3, 10.4, and 10.6 over the past 5 years and never noticed this issue before. My supervisor said it may be an issue with how memory is being used in the program. I figured I should post it somewhere and I will add an image as soon as it happens to me again.
Thank you,
Alec