For now I’ve removed Word Reference as the default dictionary for all languages where it was. In most cases Wiktionary will be used as the fallback.
If you want to continue using Word Reference using the “Open in new window” button, you can add the following URL in the Custom Dictionary section of the Settings page:
https://www.wordreference.com/esen/{{query}}
The one above is for translating Spanish words to English. For other languages, edit the two language codes (the “esen” part) as appropriate. e.g. the URL for German to English would be:
https://www.wordreference.com/deen/{{query}}
I’ve also contacted Word Reference support to ask if they could make an exception for Readlang so that it can continue to display their definitions within a panel (an iframe) on readlang.com. If they respond I’ll let you know here.