Hi,
There are two deprecations to the SyntaxHighlight functionality that we deployed that I'd like to make sure your communities are aware of.
1. The <source> tag is deprecated. <syntaxhighlight> should be used instead. This means that {{#tag:source|..}} should be replaced with {{#tag:syntaxhighlight|...}} too. (https://phabricator.wikimedia.org/T237267)
2. The "enclose" parameter is deprecated, if set to "none" it should be replaced by the "inline" parameter. (https://phabricator.wikimedia.org/T241636)
Both of these deprecations have their own tracking categories that you can find on Special:TrackingCategories (e.g. https://www.mediawiki.org/wiki/Special:TrackingCategories).
There's currently no set timeline for removal, I was planning to check in again in 6 months to see how many wikis had updated their pages.
If you have any questions feel free to reply here or ask on https://meta.wikimedia.org/wiki/Tech.
Thanks, -- Legoktm