Omarchy Megamenu by Morganczech

Save the page you are looking at into Omarchy Megamenu.

Click the toolbar button, pick a space and a category, then choose Save page. Megamenu stores the page title and URL on this computer so you can open them later. The Reading List space is meant for pages you want to come back to.

The add-on sends the title and URL only when you click Save page. They go to the local Omarchy Megamenu program (gruut.megamenu) on the same computer. Nothing is sent to a remote server. The add-on also remembers the space and category you picked last time. That choice stays in the browser.

Omarchy Megamenu has to be installed, and Page save in its top bar has to be turned on. Without that local helper the button explains that saving is unavailable. Only http and https pages can be saved. Saving the same address into the same space again does not create a duplicate.