[ubuntu-uk] Icons go missing ...

[Barry Drake]

Hi there ....  I'm running 15.04 testing 64bit, on a desktop pc. For  
month or two now, the Unity launcher bar loses icons after (usually) the 
second launch of a particular program during a session.  Firefox and 
Thunderbird are two such icons.  In each case, the specified icon is 
replaced by a grey square with a question mark. After re-boot, all icons 
are restored.  I'd like to file a bug report, but I don't know whether 
this is a Unity bug, or something that is part of something Unity uses.

Any thoughts?

Regards,        Barry.