Hi @frob ,
The ULS logs are the place to check for any problems or unexpected behavior faced by developers or administrators.
But Microsoft does not provide copies of ULS logs or any access to ULS logs from SharePoint Online. SharePoint online will only give you a popup with an error message when an error is reported.
Reference:https://learn.microsoft.com/en-us/sharepoint/troubleshoot/administration/information-about-uls-log-access
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.