Hello @Thomas265738242dgn,
We understand how frustrating it can be to encounter crashes in the middle of work. I tried replicating this on my end but was unable to do so. Would you mind checking if Illustrator behaves this way with all files? Also, kindly try the suggestions shared in this help article (https://adobe.ly/3LNhlJU) and check if it helps.
If the problem persists, please submit the crash report using your Adobe email address and share it here for quick tracking. The steps are shared here: (https://adobe.ly/4dpim6A). We appreciate your time and patience in helping us resolve this issue.
Thanks,
Anubhav