Doesn't this app have a setting for the default browser as there is nothing that Firefox can do to prevent another browser from setting itself as the default browser ?

Thanks for the reply. I have marked the Default Browser in Firefox settings. In the Android device settings, Firefox is the default browser. Samsung Internet is listed there too, but Firefox is set as the default. The problem hasn't occured in the last day or so, but that's usually the case. Then out of the blue, if I select a web link in a random app, it opens Samsung Internet as if it were the default. Then the default setting in Firefox settings is turned off. The Android device settings show Samsung Internet as the default. I might add that whenever the Galaxy Store offers an update to Samsung Internet, I don't update. It's so intermittent making it very annoying.

This problem is on Samsung. I don't know why but I'm having the same issues with Samsung browser always changing the default browser to theirs. I've done all the same setting changes going to Firefox, changing it to the default browser, going to my settings in the phone going down to default apps changing browser to Firefox sometimes Firefox isn't even listed I have to set the default browser in Firefox first then it shows up in the default apps on the settings. Somehow Samsung has rigged this thing to constantly change the default browser back to Samsung browser. It is extremely annoying and aggravating I'm going to their help service to find out how to fix this. I doubt that there will be any kind of a workaround.