Personally I'm using it on classic and it's working pretty well

That's good to hear! I'll still need to make a Classic specific release for Curse but this is good news.

From Curse:

Really loving the look of your addon. Im trying it out on Classic (fully aware that it is made for retail) and i am having an issue with the editbox not appearing. So I disabled all other addons which resulted in the addon not loading at all. I have no idea what is wrong but i get some error messages. The first one is saying: " attempt to index upvalue 'QuickJoinToastButton' (a nil value)", and the second is saying: "Interface\AddOns\Glass\Glass\Modules\EditBox.lua:41: attempt to index field '?' (a nil value)". I hope you find the time to turn it into a Classic addon as well at some point :-)
Cheers

Yeah probably another addon, mine is way too large but it's there.

Edit: Well the runecloth icon in that screen is way too off since it wall scrolling for a new message, but yeah the icon offset setting dont seem to work in classic. Oh and if ever it's possible to do something so it dont necessarly scroll down on new message, it can be a pain when you're trying to read something send earlier.

I stopped receiving LUA errors by commenting out references to UI elements not in classic. Namely:

• line 57 and 58 in MainContainer.lua
• line 41-43 and line 48-50 in EditBox.lua

I still can't see my chat input but I think that may be due to another addons settings that persists through being disabled.