For v1.5.2 zoom is not remembered per site. Reported by alphabetabase.
by alphabetabase on November 15, 2014 · permalink · translate
Bug introduced with 1.5.2, zoom level is not being remembered per site.
Otherwise, great addon, just using 1.5.1 for now.
For v1.5.2 zoom is not remembered per site. Reported by alphabetabase.
Source: https://addons.mozilla.org/en-US/firefox/addon/mousecontrol/reviews/645960/