I have tried the shortcuts that you have provided on my own Firefox. They appear to function correctly.

This issue could have been caused by an extension that you have installed on Firefox. To see if this is indeed the issue, please try Firefox in Safe Mode.

Does the "Ctrl + Page Down" shortcut work?

• https://support.mozilla.org/kb/Keyboard+shortcuts
• https://support.mozilla.org/kb/Mouse+shortcuts

I started Firefox in safe mode and after that everything works OK. An addon (ADBLOCK) was removed. I installed this addon again and everything still works OK. Thanks

I still have this problem. I am playing a game from this URL: http://www.freegames.ws/games/boardgames/mahjong/freemahjong.htm After loading this game it is working, but after I have clicked on the first "card" this tab is "locked", I can't use keyboard to change tab or use any menu.

That is because that website is using a plugin (Flash) for this game (that full page is created by Flash). When a plugin has focus then the plugin processes all key presses and it is not possible to use the keyboard for other actions. You will have to click with the mouse outside that game (in this case the user interface) to remove the focus from the plugin.

Earlier I used Internet Explorer and I had no problems there with Flash.

IE uses a different ActiveX version of the Shockwave Flash plugin and may behave differently when a plugin like Flash has focus.

• bug 78414 - (PluginShortcuts) Application shortcut keys (keyboard commands such as f11, ctrl+t, ctrl+r) fail to operate when plug-in (flash, acrobat, quicktime) has focus

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