I've been having these issues since One Tamriel went on the pts. I watched Youtube videos from pts, I watched streams of trials on the pts and no one had these issues. I asked guildmates but they also said there's nothing wrong on their end.
So naturally I thought maybe some files got corrupted, so I did a repair, it verified all the files but nothing changed. After this I even did a full reinstall but it also had no effect.

Issue 1 (smaller but annoying): anything quest related doesn't show up on the map.
There's no quest arrows, the show on map option just shows the zone map zoomed out all the way out, daily quests didn't even discover the delves I was sent to, I had to walk to the entrance of group dungeons because they did not have a wayshrine available to their part II.
I couldn't find any option that would've let me turn these off accidentally. There's no quest option at the map filters, there's nothing in setting/gameplay or settings/interface, there's nothing in usersettings file.

Issue 2 (almost gamebreaking): almost all particle based skills are broken in a way, they are either:
-they play their character animation properly and effect enemies normally, they just don't have their particle effects: venoumous claw/burning embers
-lights up the area but no particle effects: burning breath, wall of elements
-gets stuck in the air as a small lightsource from where it was fired, causes health bar desync for me and the mobs: destro staff light and heavy attacks, vampire's bane
-same as above but also character freezes during skill animation: funnel health and impale

I tried all graphics presets from ultra-high to minimum and it made no difference.