On: Agatha Christie could afford a maid and a nanny bu...

[contravariant]

For some reason I didn't expect you to list them from right to left.

[pajko → contravariant]

It's "automatic", see https://www.w3.org/International/articles/inline-bidi-markup... and https://unicode.org/reports/tr9/

However that algorithm has a couple of flaws in mixed left and right ordered text, and a couple of control characters have been introduced to solve the issue: https://www.w3.org/International/questions/qa-bidi-unicode-c...

Could play a bit in https://www.babelstone.co.uk/Software/BabelPad.html to see how things work.

[contravariant → pajko]

Ah is that what it was. Mixing ltr and rtl text always trips me up. To make matters even weirder it seems that sequences of nummerals, such as ١٠ are ltr again. That has some very unintuitive consequences when you try to edit that sentence.