There are a bunch of clipboard manager apps and add-ons available for Linux but the one I keep coming back to on Ubuntu is called Clipboard Indicator.
This is a GNOME extension that (like you’d expect) keeps a log of items you copy to your clipboard. This way you can quickly sift through a list to copy/paste something someplace else at a later date. What makes this exact extension especially useful is it’s fully searchable right there from the top bar.
But I don’t think you should install it.
Instead, I think you should try the newly-released Clipboard History GNOME extension.
Clipboard History is built by developer Alex Saveau (aka SUPERCILEX) who also works on the Clipboard Indicator extension. Several performance-minded changes Alex hoped to introduce to the original were considered a bit too “major” (the extension has many satisfied users, after all) so a ‘sequel’ extension emerged.
Clipboard History uses a “…compacting log and linked list to store data, enabling minimal O(1) performance for almost all operations.” Alex explains the reasoning and impact of this in a post on his blog (which is well worth a read if you’re technically inclined).
Whether you’re a convert coming from the forerunner or new: Clipboard History is simple to get to grips with (though it currently only supports GNOME 40+). You install it, then let it do its thing: log your clipboard.
You can open the applet by clicking the icon in the top bar, or by pressing the shift + super + v shortcut. You can configure all key aspects of the add-on, like how long clipboard previews are, how many entries to remember, clipboard history size, and whether it should be shown in the top bar at all.
Grab the latest release from GNOME Extensions website, or fetch the source code from GitHub.