Summary of Changes

Even though #__updates has changelogurl column, it's never updated on extension manifest update or extension update.
If extension was initially installed without <changelogurl> in manifest, next updated with <changelogurl>, the further updates are displayed with empty changelog.

The problem is that if an extension is initially installed without <changelogurl> but with <updateservers>, the changelogurl column in #__updates is initially empty and is never updated on new version install or manifest refresh.

This column is actually useless and it's easier to always use changelogurl from #__extensions which is already auto-updated.

Testing Instructions

Install new extension without <changelogurl> in manifest but with working <updateservers> URL

Update extension to newer version or install new version manually, but with filled <changelogurl>.
Or, add into manifest and refresh manifest cache.

Next, release new extension version and check updates.

Actual result BEFORE applying this Pull Request

See the update is available but Changelog is empty.

Expected result AFTER applying this Pull Request

Update is available with Changelog badge.

Link to documentations

Please select:

• Documentation link for docs.joomla.org:

• No documentation changes for docs.joomla.org needed

• Pull Request link for manual.joomla.org:

• No documentation changes for manual.joomla.org needed