That is a limitation of the native [details]
markup rule, so I don’t think it has anything to do with IME2Furigana? The HTML workaround also works with IME2Furigana:
<details><summary><振>[ふ]り<仮名>[がな]</summary>Hidden text</details>
振り仮名
Hidden textNative markup is also incompatible with [details]
, so IME2Furigana is not even a special case:
[details="Some **bold** text"]
Hidden Text
[/details]
Some **bold** text
Hidden Text
The workaround you have linked for blurred furigana is not possible to achieve with furigana markup, but it does not work that well anyway since it places the furigana below the base text instead of above:
Like this?
That’s right.
Looks for me like
Originally, IME2Furigana only converted IME input to ruby – I added the furigana markup functionality half a year later, but did not want to increase the number of modes you have to go through when clicking the F button, so I kept it at the three existing modes. Maybe I should at some point add a proper settings menu for this script so that it can be more customized. For now, you would have to disable IME2Furigana, write your post, and then reenable it before sending your post.