Unable to add items to inventory list

Had this start while setting up a character on the classic dnd 5e sheet; whenever I attempt to add another one, I can add an item, enter the name into the text box, then when I click off it, the box and new item vanishes. This continued through closing and re-opening the sheet.  It seems to have been fixed by refreshing the entire browser tab.

If this is the D&D 5E  (Classic) sheet, I've had players experience this exact problem when using a browser other than Chrome or Firefox . They also could not drag-and-drop items from the compendium onto the equipment list. The problem went away when they switched to one of those two supported browsers. Note: There are several browsers that are Chromium-based, but they are not the same as Google's Chrome browser, which is also Chromium based but with a lot of proprietary code added on.

Yes; it IS the 5E "classic" sheet that this happened on. Strangely though: I AM on Firefox... so theoretically compatibility shouldn't be an issue?

I agree that it's probably not the browser. I'd go down the usual checklist: Try Chrome, try clearing cache, try using private (Firefox) or Incognito (Chrome) mode, and logging out of and back into the site. Other than that, hopefully someone more knowledgeable than me comes along with a better answer.

Hi Mako,  Can you PM me an invite to your game? I'd like to take a look at the Character.