Improve guidance on the grammar and capitalization for headings
Headings have a particular grammatical format, like a newspaper headline, which differentiates them from regular sentences.
If you have a line of text which plays the role of a heading (large text, above other content) which is written grammatically as a sentence, it should use sentence capitalisation and not header capitalisation (though without the full stop (aka period) at the end of the sentence).
We should add this to the HIG, along with some pointers on what the grammatical rules for headings are (possibly borrow some points from this - https://englishlessonsbrighton.co.uk/8-grammar-rules-writing-newspaper-headlines/).
Edited by Allan Day