For transifex projects included in HUBs like Opentraslators the contribute now link goes to a worng URL

test it:
1- enter: Translations for CTransifex - https://compojoom.com/downloads/languages-cool-geil?view=project&id=8

2- click any contribute now . You will end with a "Page not found"

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This is caused on different URLS when projects are with Opentranslators HUB
on project (https://opentranslators.transifex.com/projects/p/compojoom-ctransifex (also tested with my own setup site and other projects)

cTransifex projects point to:

https://opentranslators.transifex.com/projects/p/compojoom-ctransifex/language/ca-ES/

but Opentranslators language pages for that project is

https://opentranslators.transifex.com/projects/p/opentranslators/language/ca_ES/?project=7119

Note: the non Opentranslators projects are fine with cTransifex, as in

https://www.transifex.com/projects/p/djimageslider/language/pt-PT/