Lol, if you think it might be a malicious page... I'm - not- volunteering to go.
XDA is a reputable site packed full of coders so while not impossible it will get taken care of.
More than likely you got "it" somewhere else...
Yes a hard reset kills everything except if you load it back in afterwards. If there's an issue be it settings or malware it's best to ID it first. If comes back you'll be right where you started.
Short of downloaded evil thing Android is pretty robust to malware; even with a completely outdated KitKat running for 2 years I never had to wipe a drive because malware.
6 years straight on Androids with no unfixable malware or trojans.
>Clear all data in that browser, reload it if it continues to behave strangely.
>Boot menu> System Cache, clear it and reboot.
>Download from Playstore Stuborn Trojan Killer and Malwarebytes, run both and see what they pull.