In the meantime, I have two workarounds/mitigating techniques to suggest.

One, you can type part of the web address/page title in the Location bar, and now in Firefox 4 any open tabs you have matching history search will filter to the top so you can quickly find and switch to the tab you intend to without having to hunt for it. Efficiency Tip: On systems running Windows (incl. at least xp, vista, & 7), F6 cycles through windows elements, which may help you more quickly get to the Location bar (especially if you Customize it's location to the left of the default Tabs location, as F6 will then move the cursor right into Location).

Two, you can put no-icon/same-icon tabs in a known [sensible/e-z to remember] order (possibly with a handy crib, e.g. sticky note, stickers above/on keys) and use the Ctrl-[1-8] keyboard shortcut to access the first 8 known webpage unmarked tabs quickly & without guesswork.

Hope somebody else finds this helpful!

See also:

• Bookmark Favicon Changer: https://addons.mozilla.org/firefox/addon/bookmark-favicon-changer/

Bookmark-FavIcon-Changer is a cool helper add-on but unfortunately it does not help with this particular issue since it apparently cannot change the icon displayed on an App Tab (at least not at the time of this reply ;-)

I have the same problem. Theoretically, remembering the order of the tabs should be enough. I think we all know it isn't, though. In the age of customizable everything, pausing to recall what goes where just doesn't cut it. Seems like there's probably a cool and quick work around here, but I haven't come across it yet.

Is there anywhere to get actual support instead of just commiserating with all the other users having the same issues?

@Edwidget: If the developpers of the original webapps would do the job to add an icon or at least a decent name, then we wouldn't be looking for a workaround.