Drupal 8.x

I have a SPA developed in Angular that I'm looking to manage using Drupal 8.

The SPA is integrated with an e-commerce platform and leverages API calls to render various elements on the site.

Looking to manage/author the site contents/look/feel using Drupal.

I am using Drupal8, Commerce 2, Commerce Recurring and Commerce Licence. 

I am selling yearly subscription.

Issue and Steps

• User can add subscription product into cart
• User redirecting to cart page
• User hits back button and visit product page(subscription page) again.
• User again add subscription product into cart. 
• Then user end up with 2 same subscription products into cart. Need to restrict user to add multiple product into cart.

Possible solution:

Hello,

I wish to have a bibliography handled as it is in TeX: a bib file somewhere, in the text I call \cite{ref} and a bibliography appears.

\cite{ref} is transfromed into a well formed expression in the text, that it only depends on a key attached to the full reference in the bib file, and the bibliography lets appear only what I have cited.

Any idea of a module doing this?

Thanks,

-Fred

We dump database and also copy all drupal codes to another server, and when launched the new website, it shows below error with message like "Entity_bundle:node" plugin doesn't exist.

Any one how to resolve this? 

I have ticked the "enable debugging" checkbox.

When I send a test email I see a screenfull of messages flash on the screen and then disappear.

How do I make them stay on the screen for me to read?

Or are they stored somewhere else?