@codinghorror , I just noticed this: I cannot drag-and-drop text from another place into a reply that I am composing. Copy-and-paste works fine, but not drag-and-drop. While creating this thread, I see that I also cannot drag-and-drop text into the Title text box.
I happened to notice this while trying to insert an oddball character. This MacBook has a special-character app and Firefox has a menu item to open it. In this app, I cannot copy a character to the clip-board, but I can drag it. Thus, I could not insert the special character by either method.
As for that special character, BTW: I was trying to insert the Registered Trademark symbol, (r). As you can see here, typing (r) doesn’t seem to work. Nor does (c) give me a Copyright symbol. IIRC, these two substitutions used to work, but never entirely consistently.
Thanks for the report, @Senegoid. I am a developer at Discourse and looked into this issue. It’s a side effect of an open source library we use to allow drag-and-dropping files into our composer. For some reason, it was blocking text dragging. I wrote a fix and contributed it to the library (called Uppy, link to the fix). We need to wait for the library to release the fix before we can include it in Discourse, so I suspect it will take a couple of weeks before it makes it way here. (But eventually, it will!)