I’m running into a quirky problem where the dhtmlXScheduler control is rendering slightly larger then its div, but when it re-renders by resizing the browser or clicking any of the day\week\month view buttons, the dhtmlXScheduler displays properly. While I get the issue consistently with Firefox, IE8 doesn’t seem affected.

The basic idea is this:
















For example, dhx_cal_navline will be created with a width of 839px and then drop down to 822px which is the initial size of myScheduler.

The same code works correctly in local samples.
Which doctype you are using for the page and in which version of FF problem is occurs?

>>839px and then drop down to 822px
The 17px difference is very similar to the size of scrollbar in FF. You can try to add overflow:hidden style to the parent of #myScheduler container.