It was great for a long time, but last 6 months or more on some sites the panel is either not visible at all or it is blocked partially by some parts of the site (its under the textbox and such). I'm SO tired of this. Sometimes i even forget that i have it installed. Please fix it...
UPD: For Christ sake, its been about 15 months now ! Please please please, fix it!.. Its one of the most useful addons and its broken for forever, nothing to replace it with, it seems.
UPD: "World Clock (Digital and Analog) by Senthil Ponnusamy" is almost good enough. I'll have to use it instead for now.