As a small improvement (less surprise for inexperienced users), one can disable bidirectional text:
1) Type "about:config" into the address bar.
2) In the "Filter:" text box, type "bidi"
3) The "bidi.browser.ui" entry was set to "true" in the "value" column. To change it to "false", right-click on this entry and select "Toggle".
4) Restart Firefox.
After doing all this, the "Switch page direction" context-menu entry has disappeared.
As a small improvement (less surprise for inexperienced users), one can disable bidirectional text:
1) Type "about:config" into the address bar.
2) In the "Filter:" text box, type "bidi"
3) The "bidi.browser.ui" entry was set to "true" in the "value" column. To change it to "false", right-click on this entry and select "Toggle".
4) Restart Firefox.
After doing all this, the "Switch page direction" context-menu entry has disappeared.
(Copied from http:// ubuntuforums. org/showthread. php?t=619481)
Now the last menu entry is "Page Info" or "Properties", whose windows can be closed by pressing Escape.