Spamming Backspace and then holding Down CTRL/⌘-A causes an uncaught TypeError

[cwhitwell]

Hi there,
I've been running some tests on the SunEditor as I will be using it in my web application. First of all big props as it works really well :). I have however found some bugs and will raise a separate issue for each.

This bug is caused when you spam (press repetitively) or hold down the Backspace key, then press CTRL/⌘ + A (select all shortcut). Once this error occurs it can break other aspects of the editor such as changing font. I was able to work around this issue by blocking the backspace (keyCode=8) and delete (keyCode=46) keyDown event when the editor is empty. I suspect the real fix will be similar to this.

Error message in console:
core.js:3329 Uncaught TypeError: Cannot read property 'textContent' of null

Environment:
MacOS Mojave V10.14
Google Chrome Version 80.0.3987.132 (Official Build) (64-bit)
suneditor V2.26.0

Please see video demo attached (I've added an application to display my keystrokes on the screen).
Spam Backspace CTRL A bug.mov.zip