Problem/Motivation
When invoking $this->getTextContent() or $this->assertSession()->pageTextContains() on BrowserTestBase then the plain text page content is not correct. The text content of <style> and <script> tags is included in the page text, but it should only contain text that a human can see on the page.
The problem is that Mink just uses PHP's DOMDocument extension to get the nodeValue from the document, which extracts the text content of all tags regardless of their meaning.
Proposed resolution
Override Mink's Session class to return our own DocumentElement when the page content is requested. That way we can filter out styles and scripts when the text version of a page is requested. This also fixes the problem for assertSession()->pageTextContains() and getTextContent() in one place and we can avoid overriding the Mink driver class.
Remaining tasks
Patch.
User interface changes
None.
API changes
None.
Data model changes
None.