For those of you using hreflang for international pages: Make sure any rel=canonical you specify matches one of the URLs you use for the hreflang pairs. If the specified canonical URL is not a part of the hreflang pairs, then the hreflang markup will be ignored. 

In this case, if you want to use the "?op=1" URLs as canonicals, then the hreflang URLs should refer to those URLs. Alternately, if you want to use just "/page", then the rel=canonical should refer to that too. 

Finally, don't use a rel=canonical across languages/countries, only use it on a per-country/language basis (don't specify the "de" page as the canonical for the "en" version, otherwise we won't index the "en" version). 

There's much more about using hreflang on homepages at & a lot of information in our help center at

Edit: Some people asked about ways to recognize these issues on their site -- you can do that by using the hreflang tool as described in
Shared publiclyView activity