The content of pages made non-viewable to a user via permissions, within a visible parent, could be seen via the plaintext export option. Before v0.30.6 this would have applied only to scenarios where all pages within the chapter were made non-visible. In v0.30.6 this would make all pages within the chapter visible.
As per #2414
- Instead of user name.
- Due to issues with advanced charts like emoji zero-width-joiners.
- Could also have security concerns on untrusted instances with certain
webserver config due to double extension possibilities.
Closes#1993
Thumbnail generation would sometimes create a file larger than the
original, if the original was already well optimized, therefore making
the thumbnail counter-productive. This change compares the sizes of the
original and the generated thumbnail, and uses the smaller of the two if
the thumbnail does not change the aspect ratio of the image.
Fixes#1751
