How to show search result positions on scroll bar in Firefox?

It's now possible in Firefox 87.

However: it only works for web pages and not for PDFs, unlike in Chromium Edge for example.

References:

• Firefox 87.0 release notes

The “Highlight All” feature on Find in Page now displays tick marks alongside your scrollbar that correspond to the location of matches found on that page.

• ghacks article
• Firefox bug tracker

Thought it might be fun to implement this during the break. With the above patches, the tick marks are drawn in a window's scrollbar using the highlight colour which defaults to something magenta-like. Note that the 'Highlight All' toggle on the findbar needs to be on for the tick marks to appear.

You can use the HighlightAll extension. Go to about:addons and choose Custom highlighting and Show search markers. Then visit any page and make a selection (e.g. by double clicking a word). This is not the same as in Chrome, but should cover many use cases.

The license is GNU GPL 3.0 There is no public source code repository, but the source code can be inspected by extracting the xpi, as it's a zip file. Fortunately, the core add-on and libraries source files are well-organized and not minimized.

[final edit, 2022]: As already highlighted in the correct answer, FF has this feature built in since V87. DEPRECATED INFO: highlightall was until FF V87 the only tool that had the extension .

It still required the some access rights:

• Access your data for all websites
• Read the text of all open tabs
• Display notifications to you

[all other information deleted, as obsolete] highlightall still "highlights all" occurences of a text passage on a webpage... but that is an answer to a different question

It is not possible to enable this feature in Firefox (58.0.1).

But if you're willing, you can do this with extensions. I believe there exists extensions that can do this. However I have not tested such extensions.