Cosmetic filtering have no effect

[gwarser]

On this page http://florydziak.blogspot.com/2015/10/starszy-brat.html ("popup" with article)

For example "Fanboy’s Annoyance List" ##.share-controls, filters created by picker or manually.
Filters are visible in uBlock log. Sometimes they are applied, but very rarely. Mostly on first time, when loaded in background (last time happens when juggling with filter list and reloading from uBlock log).
I know, this page is broken: sometimes stops loading on "cogwheels" screen. Sometimes buttons in top left corner are missing (<, >, g+). Browser console reports problem with x-frame-options:

Security Error: Content at https://www.blogger.com/comment-iframe.g?blogID=8681818539802867443&postID=6053747354527061714 may not load data from http://florydziak.blogspot.com/2015/10/starszy-brat.html.
Load denied by X-Frame-Options: https://www.blogger.com/comment-iframe.g?blogID=8681818539802867443&postID=6053747354527061714 does not permit cross-origin framing. <unknown>

Should this affect uBlock?

I see this for some time on Fx 41 (42, 43) on Win7, Mint17, uBlock 1.3.2rc4 with EasyList+uBlock+uBlockPrivacy+florydziak.blogspot.com##.share-controls (and earlier uBlock versions with more filters)

[gorhill]

Looks like uBO's style tag is being removed by the site. Need to investigate more.

[gwarser]

Another example http://bialy-dev.blogspot.com/2014/12/what-is-bpg.html

[gorhill]

Attaching the mutation observer to the html element fixes the issue.

Correction: the body element is not removed, rather all the style tags -- including the one installed by uBO before the DOM completely loads for specific or cached cosmetic filters -- are removed.