What do you hate the most as UI developer?
I personally hate grids the most.

I want to show a list with inclusion of multi lists of data. Why is there no magic list combiner tool that knows what I want in my mind?

Working with other "UI devs" that barely know how CSS works and rely heavily on css frameworks.
I’m not entirely against css libraries but they shouldn’t prevent us from learning/understanding css.
I was astonished when I heard one of my frontend dev colleagues come to the realization that flexbox was a part of css and that it wasn’t a Bootstrap invention (d-flex, etc.). The guy had 4 years of dev experience under the belt

repetition

Implementing whatever crazy idea designer had

Grids are a good tool for all the problems not solved by flexbox.

@black-kite I use CSS framework, tailwind to be precise, but beforehand I made sure to understand all the possibilites plain CSS has. So you got a good point, diving into frameworks right away isn't the best strategy. Also even while using tailwind, sometimes I run into cases where I must use regular CSS.

I love grid the most.

Designers & client. Can't decide which is worse.

HTML tables.
Why can't you just be normal?!

Reading about UI or frontend when actually web or HTML/CSS is implied.

From a flutter background, I would say layout builder