While this addon works in most situations, I've encountered pages that somehow stick to a 'minimum' width, so that what this extension does is merely changing the font size. Microsoft Edge does not have this issue. When I dock my browser window to half of the screen, Edge displays the content without the horizontal scroll bar, while Firefox with this extension set to auto-fit, still does. This is an example page that shows this issue:
https://bbs.saraba1st.com/2b/forum-51-1.html

Hope this is not limited by some Firefox intrinsic stuff and can be fixed.

Thank you!
Hopefully it will be at least as good as the one before FF 57 big regression.
I love the possibility to change the zoom with right click between "full page zoom" and "text only zoom", and reset the zoom with middle click.
Cheers !

This addon has problems with certain zoom settings. I visited Arstechnica.com and reduced the zoom level to 120% from the default level of 125%. The page automatically scrolls down to the bottom, and does not let me scroll up again. I did not check all zoom settings. Other websites did not seem to show the same problem.

LIKE DONALD TRUMP'S SUCCESSES, THIS PROGRAM DOES NOTHING AT ALL!

Very useful extension that gives functionality which should be built-in and native to a browser. BUT some sites don't open with this extension enabled. For example: vuejs.org

В чем отличие от стандартной функции масштабирования страницы в браузере?

Almost perfect extension. It just needs 3 more things to become perfect: 1) The 'Adjust Line Space Factor' setting should be configurable on a per-site basis (as well as a global default setting) just like the zoom factor and the minimum font size setting. 2) That 'Adjust Line Space Factor' setting should always be a 'minimum setting': it shouldn't be applied to text that already holds a greater line space factor. 3) One should be able to completely deactivate/activate the extension's operation on a given tab by means of the the Firefox UI's button, in case the extension could not deliver a good layout for that tab's content. Actually these ended up being the 3 reasons that had me try to find another extension, even though I wanted to use Zoom Page WE

Perfect add-on which zooms just as expected. The only improvement I can think of right now would be for rules to also apply to sub-domains. As it is now, if I set the zoom size for example.org, it isn't applied to sub.example.org, which I have to zoom separately. Perhaps an idea for a future option: "Apply zoom to sub-domains"?

I just want to set a simple 80% default for all web pages - with the possibility to over ride the setting if so inclined. I really don't want to go in and manually set every web page I visit.
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I was wrong, and the instruction below from the developer did indeed make it work as I wanted. Thank you.

Overall good. Suggested improvements:
+/- (zoom-in/out) controls displayed on toolbar.
Toolbar button popup should have a button to edit Options.