Lock Title

Was not presented with an input field, for the new title. [Windows 11, Vivaldi 6.5]

Works well. As Michael said it does just one thing and does it well. (My only—minor—criticism would be that it's not persistent across browser restarts, but since I rarely restart my browser that's only a minor inconvenience resetting the title on a handful of tabs every few days.)

Does exactly what it promises, and only that. Has a simple UI that takes < 5 minutes to master. A genuine productivity booster if you need to keep many tabs open. Where sites set all their page titles to begin with repeated branding blather, you can distinguish the resulting tabs by giving them titles that summarize what each tab means to you.