@aral I don't think that's possible. The only option you have is to either turn off trending hashtags or turn the emails notifications for hashtags off (but that will leave the hashtags pending and those will not be displayed in the "trending now" section).
@aral Just wanted that I finished installing v3.0.1 on mastodon.ar.al and now you have an admin setting to auto-approve trending hashtags: https://github.com/tootsuite/mastodon/releases/tag/v3.0.1
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