Paragraph Block: Issue with extensions and extraneous HTML

[duplaja]

WP Version: 5.0 RC, clean installation.

Browser: Chrome Version 70.0.3538.77 (Official Build) (64-bit)

Can be viewed: ​https://guten.dandulaney.com/2018/11/24/grammarly-testing/ (view source on blocks 2-5)

Issue:

When using the Grammarly Chrome extension, as many do (and I assume other browser extensions that behave similarly, by temporarily inserting tags with a custom class to underline spelling errors), the paragraph blocks keep the extra formatting tags (see example above, view source, blocks 2-5)

Expectations:

In the classic editor, there is no inclusion of these extraneous tags, just what is typed.

Issue was also reported here, before I realized this should probably be on Trac: ​https://wordpress.org/support/topic/paragraph-block-issue-with-extensions-and-extraneous-html/

[afercia]

Related:

​https://github.com/WordPress/gutenberg/issues/10610

​https://github.com/WordPress/gutenberg/issues/9831

[pento]

Thank you for the bug report, @duplaja! As this is already reported in the Gutenberg repo, I'm going to close this issue, so we're not tracking it in multiple places.