Solr has become a top-level Apache project and main line 
development for Lucene and Solr is happening in each 
project's git repository now:

- Lucene: <https://gitbox.apache.org/repos/asf/lucene.git>
- Solr: <https://gitbox.apache.org/repos/asf/solr.git>

If you're seeing this message then switch the development to 'main':
git checkout main

Development for branch 8x remains in the shared repository: