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how do I adjust zoom increments in Firefox


The increments between zoom levels are too large for me. I'd like to have finer control between levels. Using FF 18.0.2. Winxppro.

Ive gone to a couple of tutorials

http://superuser.com/questions/396026/firefox-how-to-change-the-zoom-increment http://mozillalinks.org/2008/06/tweak-firefox-3-full-page-zoom/

..done everything described to-the-letter, to no avail. Nothing I've done seems to change the zoom parameters at all. What am I missing?

At first I only wanted to make the zoom increments finer on webpages and was uncertain that it was a winxppro adjustment or a firefox adjustment. about:config sounds reasonable since it has fairly explicit values to change in the directory such as toolkit.zoomManager.zoomValues zoom.minPercent zoom.maxPercent

But I changed those values, and just to make sure they were having no affect I changed them very dramatically, and nothing changed.

It is not mentioned in the tutorials either that there are apparrantly only 13 increments/values available for zoom adjustment. So making finer adjustments comes with a trade off (even if I could get the values to 'stick'). If you want 13 much finer values for better control over fine zoom adjustments you have inevitably have to tighten way up on the min/max zoom extents.

Can anyone help me further with this? Do I need to start/restart firefox each time I make an adjustment to the values in about:config? Never had a need to before for anything in there.

Thanks Brad

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Firefox does need to be restarted after making most any change in about:config .

Looks like 14 settings, counting the default of 1.

Any particular reason that you need more than 14 settings?

Question owner

''Any particular reason that you need more than 14 settings? ''

As I mentioned, making 14 fine adjustments restricts the min and max zoom extents. That's an unfortunate tradeoff. It would be nice to have three times that many spaces available so that one could set finer increments while still having a useful scale of min max zoom.

Question owner

No real advice here specific to my question? All the links are repeats of the directions I indicated having followed to no avail. Why is it not working for me? Are there any addons or second party software that might enhance the zooming capabilities in FF?

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Without knowing exactly why you need so many different zoom levels, and if you need Page Zoom, Text Zoom, or maybe Image zoom alone (which can be done via a bookmarklet), I have no answer other than to recommend that you look for a suitable add-on to provide that feature. AFAIK, you probably need an add-on to expand the number of available zoom levels.

IMHO, when the current zoom code was introduced, like maybe back in Firefox 3.0 or 3.5, Mozilla left out many features which other browsers had at that time. IOW, it is an incomplete feature.
Another solution would be to have three separate Profiles, each having

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I use these values for toolkit.zoomManager.zoomValues to make fine adjustments possible:


The Default FullZoom Level extension shows them as choices in the drop down list.

Question owner

I just wanted to enhance the basic zoom function that I've used all along, which zooms text, image, whole page, using ctrl +/-.

Two primary reasons why I use the zoom. I'm 52, bi-focaled and seem continually anymore to be stabbing ctrl + as I surf. No squint sounded promising, but like I said, the zoom "setpoint" seems to wander all over the place as I go from page to page and there are three separate windows in the program for setting zoom and I don't see yet why. I set them all to 140 percent and they all end up wandering off of that point.

The second reason for wanting finer zoom control is that I'm sometimes viewing imagesof small objects on screen for general "to scale" viewing (not precision, but close enough for getting a good idea) and rarely do these images have draw/stretch corners for precise scaling. Usually one needs to hold a ruler against the screen and zoom to fit. Wide zoom increments make it almost impossible to get close to any correctly scaled image as they under shoot or overshoot. Of course the remedy is to open the image in an editor program, but that's many more commands and time taken just to do a simple scaled view of the object for a quick assessment.

Default-fullzoom-level plugin description sounds identical to "NoSquint" which I installed last night. Works pretty good for fine scale zooming since it has an option for defining zoom incremements in a single box that goes as little as 1 percent. It's a bit quirky still since 1 percent increments end up requiring ctrl + to be stabbed three times to zoom, 3 percent increments take two stabs to zoom, and 5 percent seems to be the minimum to get it to smoothy work with a single click of the + key.

But it does take some learning and is more complicated than I'd like. The zoom level moves all over the place as I surf around so its primary feature seems less useful than I'd like (until i figure out how to set it correctly)

I may have to try a few of these zooming plugins until I find one to my taste. Thanks for pointing to them.