New
#11
Post #1 puzzles me - I've never known anyone use a browser full screen on a 16:9 monitor. Web pages are usually fixed width - around 1020px - so I view Firefox etc windowed at about 1200 - 1000 px (on a 1920-1080 screen). Anything else has huge blank spaces. Although you can zoom a webpage to fill a widescreen, the vertical size would be stupid and unusable. The OP is surprised when a 1020px webpage looks tiny on a 4K screen.
When Windows 8 first came out, IIRC IE would only run full screen, and the Google logo looked tiny and ridiculous in a vast white expanse.
Surely widescreens are only used for movies + TV, Photoshop etc - and browsers should be used windowed ?
Wikipedia is one of the few websites that use % layout - and so Wiki can be dragged to fill a screen of any size/aspect. It is hard to read on widescreen IMHO. You can even stretch Wiki across an extended desktop . . .