Shopify's app store does not have any specific restrictions on proxy server apps. However, it is important to note that Shopify's terms of service prohibit the use of apps that violate third-party rights, such as trademarks or copyrights. Additionally, any app that interferes with the functionality of Shopify's platform or violates their policies on fraud or spam would not be accepted.
As long as your app complies with Shopify's terms of service and does not violate any third-party rights, you should be able to submit it to the Shopify app store. It is recommended that you thoroughly review Shopify's policies and guidelines before submitting your app to ensure that it meets all requirements.
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