Inline - defaults to Heading 3

Is this a feature, or a bug?

I kind of find it annoying - because its messing with my document outline - but conversely, I could understand how having default to heading 3 would a feature for your document outline.

Its a feature I’ve only just started using, so am I not familiar with the product feature legacy of - but its proving ‘faffy’, for want of a British turn of phrase - and its not playing nice with bulleted listed either.