How to save and set as default changed ue5 ui colors

the current ui is way too dark for me. So in editor preferences, i made a new theme, saved it, set as default, and exported it, but in other projects importing doesnt do anything, not does it see the new one i created(active theme) and not only that, closing the one i changed and re opening reverts to ue5 default colors.

what am i doing wrong here? or it simply doesnt work yet?

ps- i couldnt get ue5 tag to work so i had to use ue4 (forum)