This extension will save automatically the content in textarea or WYSIWYG editor when user is typing. User can recover the saved texts in the cache window, even the tab or the window is closed unexpectedly.
It would be useful to have the Textarea Cache button on the toolbar. Please open the toolbar context menu (for example right-click on the toolbar for Windows and Linux), and click "customize", then drag the Textarea Cache button onto the toolbar. The button is grayscale when the cache is empty. When you start to type something on a textarea, the button will become colorful. Click the button will open the Textarea Cache Window. You can also open the Option Window by clicking the small arrow next to the button.
If you prefer a small icon on the add-on bar (on the bottom of Firefox window, you need to turn it on by pressing ctrl-/), you can check the "Show statusbar icon when texts are saved in the cache" option in the option window.
If you prefer a small icon on the add-on bar, but you want to customize its position, please drag the Textarea Cache toolbar button onto the add-on bar.
For people who need password protect:
"Lazarus: Form Recovery" is your better choice. see:https://addons.mozilla.org/firefox/addon/lazarus-form-recovery/