Hi pdesanctisiii, not the Program Files, but your ''profile folder.'' These articles have more information: * [[Back up and restore information in Firefox profiles]] * [[Recovering important data from an old profile]] Now... Firefox also has a Sync feature when you connect two installations of Firefox to the same Firefox Account. Please make a backup first! But assuming it works correctly, your open tabs should transfer between the two Firefox installations. ---- ''Other Session File Notes'' When you are looking in your profile folder, you'll notice a lot of different files in the '''sessionstore-backups''' folder. Here's a general description: * recovery.jsonlz4: the windows and tabs in your currently live Firefox session (or, if Firefox crashed at the last shutdown and is still closed, your last session) * recovery.baklz4: a backup copy of recovery.jsonlz4 * previous.jsonlz4: the windows and tabs in your last Firefox session * upgrade.jsonlz4-''build_id'': the windows and tabs in the Firefox session that was live at the time of your last update I have a tool to convert one of those files to a clickable list of links you can use as an archive/backup for re-opening tabs if the file copying methods and Sync are not successful: https://www.jeffersonscher.com/ffu/scrounger.html After you drop a file on the page, click "Scrounge URLs" to generate the list (hopefully; sometimes it can't handle really large files, in that case reload and try the Unstructured URL list). Use the Save List button to save the results to an HTML file.