Modifier Key in accelerator key tooltips is incorrect for Firefox on Linux.

The accelerator key tooltip given when hovering over a button or other control specify a modifier of "Shift + Ctrl" on all versions of Firefox on Linux. This is not correct.

• For Firefox versions < 2 the correct Modifier is Alt and
• For Firefox versions >= 2 the correct modifier is Shift+Alt

It is worth noting that users can change the default behaviour using about:config, but that is beyond our control and scope.

See: https://bugzilla.mozilla.org/show_bug.cgi?id=349716 for a long discussion of the change from Firefox 1.5 to 2.0.