Measure option in firefox?
You can download the web developer dashboard . It has a built-in ruler. After installing it, it will appear in your menus in Firefox. Click on miscellaneous, then click the display button.
You can also try searching for "pixel ruler".
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Not a Firefox extension (it's a Windows app), but you can try Ruler . It's also just that it does what it says. You don't even need to install it, just click and use.
It can stay on top of other windows, you can drag the borders to resize and switch between vertical and horizontal rulers. You can even open multiple instances.
I had the same problem with MeasureIt, it stopped working with some Firefox updates. I found the Leader and am happy with it so far.
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Since I updated Firefox Developer Edition, I have had severe incompatibilities with my previous add-ons.
The Measureit add-in is one of the extensions that does not update in a new browser.
I found this alternative which works fine, but not as good as Measure it. https://addons.mozilla.org/en-US/firefox/addon/browser-ruler/
If you are using the Firefox developer option, click the tools icons> select Get More Tools> Search and add it.
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