A few days ago I made my yearly move from Safari to Firefox. It starts up quicker for me than Safari and web pages load 2-3x faster.
However, I was stumped today when I wanted my Mac to read me a Flash 101 tutorial. I went to Firefox -> Services -> Speech, but “Start Speaking Text” was grayed out.
After a quick Google search I found a simple 2-step solution (thanks to aynmensch @ mozillazine): setup a shortcut key for “reading selected text” which can be evoked within Firefox.
1) Open System Preferences –> Speech
2) Click “Speak selected text when the key is pressed” and then “Set Key…” to create a keyboard shortcut (I use command+option+control+s).
3) That’s it! Next time you want Text-to-Speech in Firefox just highlight the desired text and click your keyboard shortcut.