Theme development

I have a site with Drupal 8. I am an anonymous user. I am visiting the page "Messaging" which is accessible only to the authenticated user. The page displays a code 403 with a block to connect me.

When I connect, I arrive on the homepage of the site.

I created a 403 custom page with a "Connect" button in a Twig file of my theme:

<a class="use-ajax btn btn-success btn-md" href="/user/login" data-dialog-type="modal">Se connecter</a>

How to make the user who logs on a 403 page, return to the current page?

I'm using Drupal 8.6.9 with a Bootstrap sub theme and I've enabled a forum on my site. Unfortunately the forum page does not have any CSS

styling. Could someone provide me some guidance as to how I can improve the look of the forum page...?

Submenu is not expanding on mouse click --- I followed all the normal steps to fix like going to main navigation block configuration Visibility level 2

Here is my Header Section

I was using last years Bootstrap (after changing from Adaptivetheme) - from Bootstrap CDN - and Overwriting almost all styles I needed in my own styles.css ..... and often angry - that some Bootstrap CDN elements are trying to come into my CSS way... and also - that Bootstrap CDN seems loading a LOT of unnecessary staff for me, that I have to overwrite, and then - why is it even loading that unnecessary staff?!

So.... yesterday I downloaded Bootstrap library and put it locally.... my site is anyway on cloudflare.... so I hope the performance impact should be minimal....

Hello,

In my theme, I wanted to output an img tag with the image's src attribute. I found that the way to do that is (example):

file_url(content.field_example_image['#items'].entity.uri.value)

So I have installed Twig Xdebug (https://www.drupal.org/project/twig_xdebug) and looking at the debugger, neither the image (field_example_image) nor its array (field_example_image['#items']) have a member called 'entity'. So where does the 'entity' coming from?

Hello drupal veterans i am really i need of help here i feel like taking down my site and recreatting it using another cms but first i came here

okay i developed my website locally before moving it to a live server. everything was okay in localhost but since uploading it, its been a hell.