Firefox:
- https://addons.mozilla.org/en-US/firefox/addon/toomanytabs-saves-your-memory/
- https://addons.mozilla.org/en-US/firefox/addon/onetab/
- https://addons.mozilla.org/en-US/firefox/addon/autoclose-tabs/
- https://addons.mozilla.org/ru/firefox/addon/suspend-tab/
- https://addons.mozilla.org/en-US/firefox/addon/all-tabs-helper/
Safari: