Install script manager in your browser
For example:
- Tampermonkey for Chrome, Firefox, Edge, Safari, Opera, Dolphin, UC
- Violentmonkey for Chrome, Firefox, Edge, Opera, Vivaldi and more Chromium based browsers
- Greasemonkey for Firefox
What next?
- Open a script you are interested in and install it in your script manager.
WordPress Customize Panel Resizer
Userscript to change the minimal width of the customization panel in WordPress.