I started this thread because I believe it may be related to these problems/failures I'm having with exporting /importing Bookmarks, uploading images (on this site and elsewhere), which has also on occasion led to crashing my pc. [https://support.mozilla.org/en-US/questions/1458505 Images from my previous thread auto-uploaded to this thread]. I felt it might be better to separate the conversations until we get motre info. Thru trial and error, it seems all these symptoms I will describe seem to be linked to my sessionstore.jsonlz4 file. About six months ago I was having major problems with Firefox, navigation issues, broken toolbar buttons, blank toolbar button spots. I first tried to revert to a good working backup profile, which was fine until I did the file transfers from the problem profile to the backup, after which all the symptoms resurfaced in the backup profile. . I do what I always do by transferring certain files, but only those that make the transition without creating problems/conflicts; sessionstore.jsonlz4; places, cookies, etc. I eventually chose to build a fresh profile, but the same problems occurred after the file transfer. Thru trial and error, I discovered that sessionstore.jsonlz4 was the root of the problems. I eventually went back and used the sessionstore.jsonlz4 from the backup file, but it was a real ordeal getting my session back up to date. A couple weeks ago I started having problem here uploading images. I would select the file, but nothing would happen, and I was getting all these strange side effects. But a few days later, Once again, I swapped out the profiles, these sorts of things started happening when I tired to export/import bookmarks [https://i.postimg.cc/VNGCYTZW/export-bookmarks-A.png link text] If I move the cursor over the top of the screen, a bit more appears [https://i.postimg.cc/cCYgBJxF/export-bookmarks-B.png link text] I'm writing in the backup profile now, because trying to upload from here or from [https://postimg.cc/XZ5JL2br/fe070311 Postimage], generates only these, [https://i.postimg.cc/SNhJpkNp/export-bookmarks-CC.png link text] or various distortions, i.e., but no ability to go any further in the process [https://i.postimg.cc/pTWqSghQ/export-bookmarks.png link text] I didn't have any problem transferring the history, cookies, or bookmarks to this backup profile, but how do I go about fixing this without sacrificing the session. Is there a way to import only the session tabs without bringing in the corrupting elements? BTW, still no "Preview Post" link on this page unless I '''submit '''this message first.