One of the rather logical models of using the browser for all kinds of research involves opening a new window for each of the topics. At the same time, tabs allow you to work with many documents in one window. This is a great way to organize work, and after the release of Firefox 3 with its excellent memory management, an open window with a theme that had to be postponed for a while can be left indefinitely until the time comes again.
But there are problems with working with many open pages, one of which is the inability to search in all tabs at once. Any developer working with any decent IDE is used to such a search. The search area can always be set there, and the results will be displayed in a separate window/panel and will be provided with hyperlinks to the fragments found.
It is this problem that the Find In Tabs plugin for Firefox is designed to solve. It allows you to switch from the search mode on one page to the search mode for all tabs and back with a single click, and it adds the function of highlighting the found text, which is very convenient for quickly finding the desired text fragment.
I find this feature extension to be a great tool to speed up research and just search work.
Find In Tabs