"Text (Formatted, long)" are falsely marked as changed

Problem/Motivation

When using a "Text (Formatted, long)" field type, it will in some HTML always return as changed. I think this is because the old_value is inlined without any line breaks. The new_value is apparently using line breaks.

Steps to reproduce

• Create a node type with a Text (Formatted, long) field.
• Create an observer and make sure it's being attached and notified.
• Add the following HTML to the field and save the node.
• Go ahead and again save the node.
• Now note, that even when we now do not expect the field to be marked as changed, it is actually returned in your observer from `getChangedFields()`.

HTML:

<ul>
	<li>This is a test line.</li>
</ul>

Proposed resolution

I'm having the feeling this is a core issue since I notice that in ./src/EntitySubject.php:100 the values are simply being retrieved via core's native Field API. This could also be a project specific issue, but I cannot see how that would be the case at this point. But in that case, I'll report back here.

Remaining tasks

• Check where this discrepancy is originating from (core / changed_fields / project specific)
• Write fix.

User interface changes

N/A

API changes

N/A

Data model changes

N/A