Just before I got the message We've upgraded Firefox in the background, causing me to have to close and reopen Firefox, Firefox , which I use to get mail from Outlook over my objections, dumped into the folder I had open at the time a folder called 'Mail'. Its contents are a huge number of files with the extension js, 25Mb worth. I have put this in the trash. But before I knew it was there I backed up my files on a second laptop. There the folder and its contents do not respond to -- do not allow-- the command to put in trash. The file names are grey so that they cannot even be selected to trash them. How do I get rid of this stuff? If I don't get rid of it, I daren't back up the files of that computer onto mine because I'd get it all back. So there is some urgency to the question. Sample file listed: Mail - Robert Thomas - Outlook_files/profilephotopicker_without-react_0497945b6204f57b88e6.js