This bug appeared because Django removed the setting USE_L10N in version 5.0. We had it set to false but now this setting can't be disabled anymore. We also had USE_THOUSAND_SEPARATOR set to true. Now hidden primary key values in forms are formatted as 12.345 instead of 12345 breaking the form.
I disabled USE_THOUSAND_SEPARATOR and I changed the templates to use unlocalize for these numbers (as a precaution).
This bug appeared because Django removed the setting
USE_L10Nin version 5.0. We had it set to false but now this setting can't be disabled anymore. We also hadUSE_THOUSAND_SEPARATORset to true. Now hidden primary key values in forms are formatted as12.345instead of12345breaking the form.I disabled
USE_THOUSAND_SEPARATORand I changed the templates to useunlocalizefor these numbers (as a precaution).