FindBar Tweak Alternatives
FindBar Tweak is described as 'Tweak your FindBar the way you like it!' and is an app in the web browsers category. There are five alternatives to FindBar Tweak for a variety of platforms, including Mac, Windows, Linux, Firefox and Waterfox. The best alternative is Context Highlight, which is both free and Open Source. Other great apps like FindBar Tweak are Fastest Search, Scrollbar Search Highlighter, Search Multi Tabs and SearchWP.
- Free • Open Source
- Mac
- Windows
- Linux
- Waterfox
- Pale Moon
- Firefox
Context Highlight is a Firefox extension that allows you to highlight all instances (within a webpage) of a word, several words, or a phrase that you currently have selected. Right click anywhere on the page and choose "Clear Highlighting" to reset the page.
- Free • Open Source
- Mac
- Windows
- Linux
- Waterfox
- Pale Moon
- Firefox
Best text search on page/in all tabs: count/regex/visualize & list result/find-as-you-type. Optional Instant web/history search in URLBar. Best custom search, multi-tab preview for selected text, dnd image/lnk to save/open, autocopy.
- Free • Open Source
- Mac
- Windows
- Linux
- Waterfox
- Pale Moon
- Firefox
An add-on which highlights search terms in the scrollbar(s).
Search Word position across your tabs body or title/url , then list up in sidepanel.
- Free • Open Source
- Mac
- Windows
- Linux
- Waterfox
- Pale Moon
- Firefox
Find terms entered in the search box easily with jump-to-word buttons and highlighting. Words typed in the search box are converted into buttons that can be used to find them in the current page.
Discontinued
The developer announced that he will not port the extension into WebExtensions: https://github.com/legege/searchwp/issues/113 Last version, 3.0, released in September 2016, still works on XUL-based Firefox forks like
Waterfox and 
Pale Moon
