Annoying ThunderBird behaviour

[Andrea Venturoli]

Hello.

I'm a long time ThunderBird user and since some months I'm experiencing 
a little annoying problem (on two different clients).

As you probably know, there are three menu items that can enlarge or 
reduce the font of the displayed message:
View -> Zoom -> Zoom In   (Ctrl++)
View -> Zoom -> Zoom Out  (Ctrl+-)
View -> Zoom -> Reset     (Ctrl+0)

These are bound to the mentioned keyboard shortcuts.

Very often those shortcut will stop working (i.e. pressing Ctrl++ or 
Ctrl-- or Ctrl-0 will do nothing).
It's enough to choose one of the above actions from the menu and the 
keybinding will work again... for a while.


Anyone else has seen this?
Any idea how to solve?

I'm using XFCE in case it matters.

  bye & Thanks
	av.