Default [Q] Fake the screen resolution given to a website/change screen resolution (SM-T535)

Hello,

i already thank you for reading this and trying to help me, I've started to become desperate. I have a Galaxy Tab 4 10.1 (SM-T535) (rooted) and i would like to either fake the screen resolution given to a website or change the screen resolution itself. The website I want to go on has diffenrent styles for different resolutions and it cannot be changed by just going into the sites preferences. I know it is about the resolution and not about something else because when I'm on my computer and change the resolution in the Firefox developer tools, the page has exactly the style I want on my tablet. I tried the resolution changer that was suggested in another thread, but it didn't have any effect, and I tried changing the build.prop which resulted in a soft brick.

If anyone could tell me what i could do to make a website think i have a certain resolution, that'd be great.