TopPageExtension adds an extra field to content block

[maxime-rainville]

When the TopPageExtension is applied to content blocks, it inadvertently adds an editable field to every content block.

This field is not meant to be directly editable/viewable by content authors.

This affects CMS4 and CMS5, but is especially bad in CMS5 because the extension is now on by default.

Acceptance criteria

• "Top page" field is not displayed on the front end in both CMS4 and CMS5

Related issue

• #1009

PRs

• #1042

[GuySartorelli]

PR merged. The "and CMS 5" part will be resolved when it gets merged up.