Based on our record, Rainglow Color Themes should be more popular than Slack Themes. It has been mentiond 2 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
Check this site, has a lot of themes to choose from (and install using plugin) https://rainglow.io/. Source: over 2 years ago
Looks like they have themes for other editors too. Source: about 3 years ago
Check out https://slackthemes.net/ for some ideas. You can the copy paste the values to your preferences in Slack to make use of theme. Source: about 3 years ago
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