Twenty Nineteen: heading style breaks headings in content added by core or plugins in the front end

[afercia]

The Twenty Nineteen style for headings uses some CSS generated content to draw a short horizontal line before the headings.

This comes from the post-section-dash mixin used for various elements, for example the h1-h2 headings, entry-title, author-title, and comments-title.

So far so good. But when "external" content is added to a Twenty Nineteen page, the horizontal line CSS rule targets any H1 and H2 headings.

For example, when adding the media modal in the front end, the modal headings break. See attached screenshots.

This also applies to any content added by plugins when the added content includes H1 and H2 headings.

Seems to me this CSS selectors should be better scoped to try to target only the headings within the theme content:

​https://github.com/WordPress/twentynineteen/blob/b604f127c2cae10bd48bbbec0fbbbff2cd31f957/sass/elements/_elements.scss#L55-L58

[afercia]

"select" media modal used in the front end

[afercia]

"add media" modal used in the front end

[karmatosed]

@afercia are you still seeing this? If so it would be great to get some steps to replicate as you note it is only on the front end.

[afercia]

@karmatosed the media modal dialog case is just an example. The post-section-dash mixin that adds the \020 character, which is styled as a horizontal line, may break any heading added on the front end by plugins.

I haven't seen many reports of this potential breakage. Still, scoping a bit more that mixin shouldn't be much effort.

Anyways, to reproduce the media modal dialog example:

• Go to ​https://github.com/dbspringer/wp-frontend-media click the green button 'Code' and 'Download zip'. It's an example plugin by @derekspringer
• Alternatively, use the zip I attached to this ticket.
• Activate Twenty Nineteen.
• Go to Plugins > Add New Plugin > Upload Plugin.
• Upload the zip and activate the plugin.
• Edit any post and add a Shortcode block with this content: [frontend-button]
• Save and view the post on the front end.
• Click the 'Select File' button.
• The Media modal dialog opens.
• Observe the styling of the headings within the media modal dialog is broken.

[karmatosed]

Ok, thank you - putting this to future release then for attention.