i did antivirus scan, checked all installed program and checked all addons

Firefox changing my default browser to yandex every update without asking me. Im sure i dont have any virus, add-on or apps that can cause this. Its happening after every update. Atleast ask me if i want yandex

When you keep replying as you did above, others will think someone is helping you.

Type about:addons<enter> in the address bar to open your Add-ons Manager. Hot key; (<Control> [Mac=<Command>] <Shift> A)

In the Add-ons Manager, on the left, select Extensions. Remove “ yandex “ Anything.

Also remove SafeSearch, SearchAssist Incognito, FileConverter Addon, SearchLock, DiscreteSearch, WebSearch, Findwide Search Engine, securedsearch

Now do the same in the computer’s Programs Folder.

Windows: Start > Control Panel > Uninstall Programs. Mac: Open the Applications folder. Linux: Check your user manual.