The guy who doesn't know what he is doing needs a Gareth, to explain how Travis works and how to get his code validated. We are very lucky to have people around us in Moodle. Plus we tend to help each other too which is great, as I for one have learned a great deal from Gareth.
Bootstrap 4.6 Alpha is newer than the Bootstrap 4.4 Alpha that Moodle is using. I would not worry too much as all will be OK in the end, whatever the version of BS.
I missed reading Marks post...so will go read and tge return.