This shows the keyboard shortcut configuration: https://github.com/gorhill/uBlock/wiki/Keyboard-shortcuts#ac...

The setting is called "Relax blocking mode" and will enable JavaScript (but keep all ad blockers) if JavaScript is disabled by default.

In summary, for Firefox it’s under

  about:addons > gear icon > Manage Extension Shortcuts

and for Chrome you can set it under

  chrome://extensions/shortcuts