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Loud thinking: shouldn't we set the font-face definition in the following elements?

• ckeditor5/packages/ckeditor5-emoji/src/emojiutils.ts

  Line 122 in 26bf48f

  const container = document.createElement( 'div' );

• ckeditor5/packages/ckeditor5-emoji/src/utils/isemojisupported.ts

  Line 26 in 26bf48f

  ctx.font = textSize + 'px Arial, Sans-Serif';

I think, if somebody uses a fallback font, we should also use it when filtering the available symbols.

Perhaps it can be moved as a follow up issue.

Originally posted by @pomek in #18025 (comment)

In other words, a user can define a fallback font that adds emojis even if they are not supported on some clients.

We must take care of it when filtering available emojis.