It's unbelievable but I'm been looking for something this simple as a default zoom for FF for long time.

All the others addons I've tried have no use because you either need to adjust the settings for each new website/tab etc. or the setting don't work well (i.e. when you open a new page the page is not displayed zoomed properly).

It's incredible that FF doesn't have something so basic as an option to set the default zoom for all webpages opened.

Eventually I've found this that allows you to keep the same zoom ratio and adjust the page so that it fits properly with that zoom and monitor. Simple but effective....and it works as a charm.

Thank You!