Extension mania

Discovering I can make my own browser extensions without publishing to the web store got me pretty excited. What else should I make? What kind of browser automations can I do to replace repetitive and boring tasks that I do often?

• Auto-save (for when editing Carrd) - Helps people auto-save every X minutes while editing Carrd
• Auto-refresh web page or a certain element on page, like this one I made for booking something
• My own special Twitter feed - read the text and removes the whole tweet if it catches certain keywords
• Blockers for certain types of content - Extending on the special Twitter feed, what else can I block on the internet?
• Browser dark mode - Useful when working early in the morning!

What else what else?