I have several sites where I have loaded a custom stylesheet for the Admin. They work fine in both the TinyMCE editor and the sidebars.

I have one site where the custom stylesheet targets the TinyMCE styles properly, but does not seem to target anything in the sidebar. The only variable is that I’m using JetPack ‘Free’ on this one site, which seems to somehow override styling in the sidebars.

However, perhaps I am heading down the wrong alley because I have tried deactivating JetPack (not uninstalling) and it does not seem to address the issue.

Is JetPack a likely culprit? Is there a way to prevent it from overriding my custom CSS? Or is there some other obvious issue I’m missing here?

Again: my custom stylesheet works -fine- within the DIV for TinyMCE, it is only the sidebars which are being ignored.