Bookmarks are stored in the places.sqlite file, and bookmarkbackups are in a folder with that name - both in the Profile folder.

https://support.mozilla.com/en-US/kb/Profiles#w_how-do-i-find-my-profile

I´m sorry but do you know this filename in the dutch language? I downloaded firefox in the dutch (Nederlands) language . The name of favorites in this language is "Bladwijzers"! Regards Josef

The file name is the same in all language versions of Firefox.

You can use this button to go to the Firefox profile folder:

• Help -> Probleemoplossingsinformatie -> Profielmap -> Bijbehorende map openen

Thanks, I found the file with the old bookmarks but how do I use them now?

Which bookmarks file are you referring to?

Is that a JSON backup or the places.sqlite database file?

You can copy places.sqlite to your current default profile folder, but make sure to remove any other existing places files.

If you mean a JSON backup from the bookmarkbackups folder the you need to restore that file in the Bookmarks Manager. Note that this will replace all current bookmarks.

See:

• https://support.mozilla.org/kb/how-do-i-use-bookmarks

• http://kb.mozillazine.org/Backing_up_and_restoring_bookmarks_-_Firefox

the file is called bookmarkbackups and all my bookmarks are there as json files. It is a folder within the file "profiles" How do I select ALL to restore? Now I only can take one and that will be replaced by the next one following the text.

You only need to restore the most recent JSON backup that has all bookmarks to get your bookmarks.

How do I restore that file. When I click in that file I see all the different bookmarks but i cannot gather them to restore. I can only take one and after restoring it is replaced by the next one.

Do all those backups have different bookmarks?

If you need to restore multiple JSON backups then you need to export the bookmarks to an HTML file after you've restored a JSON backup.
Then you can merge them all after you've done that with all of them.

If you need to resolve duplicates then use the CheckPlaces extension.

• CheckPlaces: https://addons.mozilla.org/firefox/addon/checkplaces/

As I wrote before, I have only one file called bookmarkbackups. If I open that file i have some 30 bookmarks json defined by different data. How to put them into a HTML file and what to do with that HTML after that?

bookmarkbackups is a folder and not a file.

Firefox creates a backup copy of the bookmarks in the bookmarkbackups folder each day that you start Firefox with a maximum of 10 (browser.bookmarks.max_backups: 10), so only the most recent JSON backup in that folder that was created before the formatting has all your latest bookmarks and you do not need to restore older copies (keep them for backup for now).

So only restore that last JSON backup and check if that gives you all your bookmarks.

• Bookmarks > Show All Bookmarks > Import & Backup > Restore > Choose File

• https://support.mozilla.org/kb/how-do-i-use-bookmarks