In the past, the sanitizer would remove unsafe elements, but still
traverse and sanitize (and potentially preserve) their content. This was
problematic in the case of `<style></style>` tags, whose content would
be converted to HTML text nodes.
In order to fix this, the sanitizer's behavior was changed in #25879 to
ignore the content of _all_ unsafe elements. While this fixed the
problem with `<style></style>` tags, it unnecessarily removed the
contents for _any_ unsafe element. This was an unneeded breaking change.
This commit partially restores the old sanitizer behavior (namely
traversing content of unsafe elements), but introduces a list of
elements whose content should not be traversed if the elements
themselves are considered unsafe. Currently, this list contains `style`,
`script` and `template`.
Related to #25879 and #26007.
Fixes#28427
PR Close#28804
Comment nodes that are child nodes of unsafe elements are identified as text nodes. This results in the comment node being returned as an encoded string.
Add a check to ignore such comment nodes.
PR Close#25879
By providing a top level sanitization methods (rather than service) the
compiler can generate calls into the methods only when needed. This makes
the methods tree shakable.
PR Close#22540