I know you don’t want to install an extension but for the benefit of others, my solution was to install the Copy as Markdown extension¹ which provides all tabs

I know you don’t want to install an extension but for the benefit of others, my solution was to install the Copy as Markdown extension¹ which provides all tabs in current window as a list of Markdown links. It suits me because I often like to take notes and save them as Markdown – as well as providing a backup list of open tabs (one list per window). ¹ https://github.com/yorkxin/copy-as-markdown https://github.com/yorkxin/copy-as-markdown