Mint 19 was made EOL back on April 1, 2023 according to https://endoflife.date/linuxmint so no more package updates from Mint including Firefox package. Unless your computer is say 18+ years old I would say it likely has a 64-bit CPU even if the system originally came with a 32-bit OS as can happen with some OEM computers. Besides updating to current Mint version, you can try the Linux tarball from Mozilla as it gets internal Firefox updates from Mozilla. https://www.mozilla.org/firefox/all/desktop-release/ It is basically a archive and no package or installer etc. Just extract it and run the firefox script or firefox-bin to start Firefox. Do not try to [lace this folder over your Firefox 113.0 package build folder as that will potentially cause problems like crashes due to mixing. Where ever you put the firefox folder make sure the folder has read/writer permissions so to get Firefox updates by the user and not root. An easy way is to have the folder in /home/ You can create a desktop launcher shortcut to the firefox-bin and you can use a Firefox icon from this folder /firefox/browser/chrome/icons/default/