It was already set as utf8_general_ci originally. Did you mean to say that?
No, I meant if you set the column from "utf-8_general_ci" to "utf8mb4_unicode_ci", post results

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As for the other part of your post... good to know

. I wouldn't set this collation as this might cause problems in future versions of SMF and database conversions from one version to another, but it's your forum, your choice

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If there was a way to block emojis from mobile devices, I would implement it on my forum, but as far as I know, there isn't one, so I just hope the members obey the "no emoji request" i posted in a thread in their PMs. As for the public part of the forum, I usually do manual edits, although I haven't done one in a while, not since I posted the request.
Just to be clear, there are no problems with emojis on SMF 2.0.x. On some browsers they load, on others, they don't (I think PPAPI browsers loaded them correctly, NPAPI didn't... well, not all of them, I usually use Pale Moon, a Firefox fork and it loaded the emojis correctly), but the topics and posts are accessible and readable. Though, I have to admit, I haven't looked in the error log :S.
So, the bottom line is, I asked the members not to use emojis as a precaution. I don't know what decisions will be made in future versions of server OSes, database managers, SMF, PHP, etc. Most likely, things will go in an upward direction (will support these symbols out of the box in future versions), but better safe than sorry

. Besides, it's not such a big deal, they could always use the ANSI combinations to generate smileys. Sure, it's a bit more complicated, but hey... that's life

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