Thanks, Anshul Saini. It actually happened most recently in Photoshop (2022). (I realize now this is an Illustrator forum, sorry, I saw fernandam88771201’s mention of Photoshop also so I pursued this thread.) So I started in Safe Mode (BTW, I have a silicon M1 Mac). Started the following programs, testing the spacebar-hand after each one: Photoshop, Illustrator. Then Chrome, FileMaker, Connect Fonts, Excel, Word, PowerPoint, Teams, Outlook, TeamViewer, even the Calculator, Text Edit, Terminal and QuickTime player, and finally InDesign. Kept them all running while I worked a while in Photoshop... bopped in and out of one of the other programs now and then... the issue never occurred. Tried checking and unchecking Accessibility “Enable Full Keyboard Access” without impact. (Also, in System Preferences, Sleep is disabled.) Of course a problem happens until you’re actively watching for it… 😛 I guess the only thing I can do when it occurs is to TRY to remember what other program might have JUST been using before that, and what I was doing.
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