i want to activate a shader on minecraft pe but when i click it an activate button doesn't show up and i've reloaded it multiple times. what do i do???

I tried it as well and the option is greyed out. It seems like some or all texture packs are not supported on bedrock mobile. This could be due to performance issues, or compatibility. I'm not fully familiar with bedrock mobile, but on bedrock desktop I had no issues.

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