[Misskey] Size of custom emojis should be limited in height, not width.

[Npepperlinux]

Custom emojis in the note are limited in width, but Misskey allows horizontal emojis, and vertical emojis cover the text above and below, so Flare should limite custom emojis height.

Misskey Web	Flare

(Fedibird, the Mastodon fork, allows horizontal emojis in reference to Misskey, so it might be a good idea to apply it to Mastodon as well.)

[Tlaster]

The emoji display for misskey still needs some rework, currently due to the limitation of the Compose Text InlineTextContent Placeholder, which requires a fixed size to be displayed, the compose-richtext does support dynamic size of inline image by using subcompose, I'll try to implement it later.