I've been getting these black-background text popups in the upper right corner when I have firefox running (they appear even when minimized) and when I click on them it takes me to pages. I'm not sure why this happens. I have 2 Extensions (Image Search Options from saucenao.com and https://github.com/bijij/ViewImage ) and 2 Plugins (OpenH264 Video Codec provided by Cisco Systems, Inc and Widevine Content Decryption Module provided by Google Inc.) so I don't know if any of these might have a reputation. They vanish on their own so it's hard to get a screenshot in time.
What seemed to fix it last time was:
delete your ~/.mozilla folder and ./config/mozilla/ and restart FF
you just lose all plugins/malware/data
this ~/. is just user data
This worked but I lost my bookmarks and logins so I'm wondering if anyone knows how to back that up ahead of time so I can add it back after deleting these folders.
Best Answer
Try refreshing Firefox instead of deleting its config files.