Best, but Closing is annoying. Please turn it on/off with a toolbar icon instead of a context menu.

I think that the extension is the best of it's kind for FF. The only missing thing is an easier way to exit the widget, like pressing the "esc" key.

Best Font Finder Addon for Firefox. The second best asks for access to read the clipboard data, so better now.

Only things which annoys me with What Font OLI is that the dialog cannot be closed by pressing the escape key or a «x» in the top right corner. Would be great if the developer would add this.

Font OLI is definitely fantastic, 'must have' for graphic and web designers

So far so good. Very similar to WhatFont on Chrome Add-On/Extensions, but with a bit more dynamic ability. Definitely the best of the Font checking apps I've found on FF so far.