Firefox change default page format

I live in Austria and standard paper format here is A4 and not Letter.
It is very annoying that Firefox does not remember the page format once I changed it in "File->Page Setup...". If I would use the german version of Firefox maybe defaults would have been set to A4 anyway - however in the english version (at least on Ubuntu Linux) the default is Letter.

Here is how to change it (to A4 in my case):

1. In the location bar enter: "about:config"
2. Read carefully and confirm that you are going to be careful
3. Be careful with the following steps!
4. In the search bar enter "paper"
5. Look for properties ending with paper_size and paper_name.
6. For me it was sufficient to change "print.postscript.paper_size" and "print.print_paper_name" to "A4".
7. There might be some additional properties ending with paper_size and paper_name for each of your available printers. I didn't touch them and it worked anyway - YMMV.

HTH.

Related posts: Locale configuration on Ubuntu, OpenOffice and LibreOffice starts slow, Default Paper Size in Open Office, Normal.dot in OpenOffice or LibreOffice.