One of the main reason why you are not seeing some or any mix at the time of posting content via chrome browser extension is that the mixes are read-only mixes. tchop doesn’t allow to add/edit anything in the read-only mixes. Please make sure that the mixes in the channel where you are trying publish content are standard mixes. You can check it from the channel dashboard:
If the tag says ‘read only’ - then the mix is read only and you cannot post any content in that mix.
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