had a dream cohost had extra customization features where you could change the background of the dashboard + your profile and there were a few extra elements around pages that you could put different images in. there was a large selection of default images on the site you could use for these things and they were all sort of low quality and had a really bizarre variety, felt like digging through the files of one of those old cd-roms that just consisted of like thousands of random images you could use.
the site was also split into several different instances like mastodon but it was more just like joining a club rather than using a distinct service because it basically impacted nothing, i think basically the only differences was that your instance appeared next to your name on posts and the default background images from before were different depending on what you joined but since you could change those anyway it didn't really matter
