Why are operators accidentally highlighted?

[OxfordStreet]

[OxfordStreet]

Hi,there!
I used mdanki .\soulmachine_anki.md .\soulmachine_anki.apkg to generate anki cards, but it started to look like above after I changed the template:"dark" to template:"default" in the file which named settings.js under ..\mdanki\src\configs
Nothing changed even I restored the template value to dark.

[OxfordStreet]

It seems like something wrong with Anki

[OxfordStreet]

I deleted the _highlight_default.css under USERNAME\AppData\Roaming\Anki2\User 1\collection.media, and it was restored to its original form:

If you delete the _highlight_dark.css, you will get something like this:

but, you can still see the shadows left by the operators~

I just deleted both files to get the plain text.