Do not check compatibiliy while upgrading

src/pretix/base/plugins.py

@@ -44,13 +44,14 @@ def get_all_plugins(event=None) -> List[type]:
 
 
 class PluginConfig(AppConfig):
+    IGNORE = False
 
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
         if not hasattr(self, 'PretixPluginMeta'):
             raise ImproperlyConfigured("A pretix plugin config should have a PretixPluginMeta inner class.")
 
-        if hasattr(self.PretixPluginMeta, 'compatibility'):
+        if hasattr(self.PretixPluginMeta, 'compatibility') and not self.IGNORE:
             import pkg_resources
             try:
                 pkg_resources.require(self.PretixPluginMeta.compatibility)

src/setup.py

@@ -46,9 +46,11 @@ class CustomBuild(build):
         django.setup()
         from django.conf import settings
         from django.core import management
+        from pretix.base.plugins import PluginConfig
 
         settings.COMPRESS_ENABLED = True
         settings.COMPRESS_OFFLINE = True
+        PluginConfig.IGNORE = True
 
         management.call_command('compilemessages', verbosity=1)
         management.call_command('compilejsi18n', verbosity=1)