fix: [wip] migrate legacy embed markup [3395]

Created by: Tirokk

Authored by rbeer Apr 13, 2020

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🍰 Pullrequest

Adds migrattion to update posts with embeds to new block level style markup; the transformation ensures paragraphs around embeds.

<p><a href=\"https://youtu.be/jB6mI8uVxKU\" class=\"embed\" target=\"_blank\"></a></p>

to

<p></p><a href=\"https://youtu.be/jB6mI8uVxKU\" class=\"embed\" target=\"_blank\"></a><p></p>

Issues

• fixes [2] of #3395

Todo

• Write migration