Feature Request

• Yes, I reviewed the contribution guidelines.

Describe your use case and the problem you are facing
For adding new file formats to scan like blade (that WordPress base themes use),
it would be nice to know what gettext/gettext version should be used.
Currently wp i18n uses gettext/gettext v4.8, v5 introduced some changes, Extractors were removed from the base package (and the concept renamed).

Describe the solution you'd like
What gettext/gettext release should be used in the long term? Are there plans to update to 5.x?