Schema des internen Link-Meta-Itemprop-URL, die die HTTP-Version zeigt

Have you reloaded? I just checked and https://defenceforum.org/t/isro-gears-up-to-flag-off-cryogenic-stage-on-march-27/300 looks good to me:

and checking under the Security tab in Chrome’s developer thing, it says “All resources on this page are served securely.”