Panic: I created two documents tonight, but they've vanished

I created a document full of over a 100 flash cards. The two document have vanished, but the flashcards are there when I open “Account” and “Cards”.

What did I do? I can’t put in all that work to have documents vanish.

Also, In the browser version, what is the tiny button in the upper right hand zone of the app that has a # symbol, an up arrow, the word “document” and an “x”? If the tiny x deletes the entire document, is there any way to recover it?

I found the “TRASH” folder, but the documents are not there.

If you clicked the x this is the reason your document is not showing. It is still there, don’t worry.

These buttons are the tags applied to the currently opened rem.
There is a special power up tag called #Document which turns a rem into a document making it appear in the sidebar and the document list.
If you still remember the name of those two rem then search and open them with Ctrl + P and reassign the document power up tag using the top right menu. (Basically reverse How to remove document tag)

If you don’t remember the name to search for (or any content they have) it gets tricky, but there is a request and certain methods to list non-document top-level rem as well: Top Level Rem Viewer

Thank you for helping me. I was able to use Ctrl+P to find and retag my list as a document!