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Normally will prevent the player from processing that recipe with quality modules in the module slots, as if you try to switch to that recipe when quality modules are present you will be blocked.

Recyclers will however, as furnaces, switch recipes automatically and continue to recycle despite quality modules being present.

The effect can be observed in https://mods.factorio.com/mod/No-Qualitycycling.

Note that this bug prevents mods from adding idempotent recycling recipes (input = output without the possibility of quality upcycling) which are likely a helpful tool in certain obscure cases.

Thanks for the report however given this is unchanged over 1.1 and previous game versions I'm going to classify this as "not a bug". If another developer wants to rework this behavior they're free to do so but until that point this is how furnaces work.