Hi mr.bakinets, * If you see “(32-bit)” and you are running Firefox 56.0 or older, updating to the latest Firefox version should automatically upgrade you to 64-bit. * If you see “(32-bit)” and are running Firefox 56.0.1 or newer, then your computer may not meet the minimum memory requirement for 64-bit (3 GB RAM or more). You can still manually install 64-bit Firefox, if you choose. You need to manually install 64-bit Firefox, you can simply download and re-run the Windows (32-bit or 64-bit) Firefox installer from the Firefox platforms and languages download page. https://www.mozilla.org/en-US/firefox/all/#product-desktop-release