Circuit visualizer stops working after some time

So far I haven't been able to isolate this problem, but basically:

1. Use Tor Browser 5.0.2 (current at time of writing), GNU/Linux, 64-bit.

   Stock, no additional extensions or addons of any sort; security slider set to high; very strict/restrictive NoScript configuration; some other minor preference tweaks.

2. Have Tor Browser running for a relatively long period, say days.

3. "Eventually," the circuit visualization is no longer there.

   The TorButton menu looks and acts normally except for the fact that the right half of it no longer shows the circuit graph, the whole menu is now made only of the 5 buttons (from "New identity" to "Check for Tor Browser update").

   This is the case for any web page, regardless of domain, scheme, etc.

4. From this point on, the only thing that seems to restore the circuit \ visualization functionality is restarting the browser. I tried "New \ identity" and "New Tor circuit for this site" with no change.

I'll try to follow up with a comment when/if I manage to identify more precisely "when/how" the issue manifests itself.

BTW, I'm pretty sure I read a comment on the blog about this (may have been months ago), though I cannot find it now.