Firefox inspector - CSS rules suggestions/hints

Question

I have a problem with the inspector in Firefox browser. After some time of use, in the "rules" tab, system don't want to show me CSS syntax suggestions. After switching the inspector off and on, everything returns back to normal, but ... again ... after a few moments, the system stops showing me syntax hints.

           with syntax hints                           without syntax hints
                                                    after a couple of minutes

Is there any FIX for this? I'm using newest "FireFox Developer Edition" (same thing on normal "Firefox").

UPDATE: I discovered that inspector starts to work improperly when I restart a page which I have been "inspecting".

Answer 1

Are you using Firefox Developer Edition 41.0a2? It appears to have possibly been a bug that is being corrected.

I can confirm this happens in Firefox 40.0.2.

I also saw this in Firefox Developer Edition 41.0a2.

I updated Firefox Developer Edition to 42.0a2 and am no longer able to recreate this phenomenon.