I tried to install littletiles, but couldn't find it on the Twitch Launcher. I then searched it up on google, and found a curseforge link, but it was listed as "not found", despite it being one of the first results. I have noticed other mods that seem to have disappeared from Curse all at once, though I am not sure exactly what happened to them. Maybe it's something that you can fix by re-uploading it to curse. Here is the curseforge page for littletiles, which is as you can see nonexistent.

https://www.curseforge.com/minecraft/mc-mods/littletiles

It's currently pending approval by the Curseforge moderation team.

Why is this mod no longer available on curseforge?
I can't believe that an approval needs sooo long.

You are not the only one, already contacted the support, still nothing.

Finally it's been approved.

Hohoho, it's back :)