Remove Scripts and Styles from DOM when empty

Good point. Thanks for the patch!

Thanks. I'll take a look later.

Hi there!
That's a very good point. Those empty styles and scripts should be avoided when not necessary.
The #4 is almost good except for the following:

+++ b/eu_cookie_compliance.module
@@ -299,15 +299,20 @@ function eu_cookie_compliance_page_attachments(&$attachments) {
+    if (empty($data['css'])) {
+      return;
+    }

You can't do this as there is some unrelated code that should be run after this attachment! (lines 322 to 340)
You should wrap the attachment creation as you did with the previous one.

Fixed #6

The coding standards test failures are not related to the attached patch.

+++ b/eu_cookie_compliance.module
@@ -299,25 +299,29 @@ function eu_cookie_compliance_page_attachments(&$attachments) {
diff --git a/js/eu_cookie_compliance.js b/js/eu_cookie_compliance.js

+++ b/js/eu_cookie_compliance.js
@@ -246,7 +246,7 @@
+    if (!euCookieComplianceHasLoadedScripts && typeof euCookieComplianceLoadScripts === "function") {

Why is this check really needed? Can we try to avoid that?

Patch Reroll on the 8.x-1.3 module version

We would also need a patch for d7.

Reroll again

+++ b/eu_cookie_compliance.module
@@ -333,25 +333,29 @@ function eu_cookie_compliance_page_attachments(&$attachments) {
+      $cache_tags = isset($attachments['#cache']['tags']) ? $attachments['#cache']['tags'] : [];
+      $attachments['#cache']['tags'] = Cache::mergeTags($cache_tags, $config->getCacheTags());

I'm not sure this code on line 357 and 358 in the patch should be excluded when there is no css config. To me this doesn't seem right. Those lines were introduced in #2669028: No cache invalidation when settings change. and are not related to the css issue at hand.

Do you have any details, @Bès or @DuaelFr?

Patch Reroll on the 8.x-1.6 module version.

Altered the patch according to the comment by @svenryen. Seems to me the cache tags should always be included?
Added an extra check in the js file: savePreferencesAction method also loads the scripts.

Looks good now, I think. Agreed that the cache tags need to be outside.

Thanks for the review. I'll commit later.

There was a script load related to the new categories feature that the patch in #19 didn't cover. I added an additional check there, as I think the script would otherwise fail.

Also, patch parted to D7 is attached.

@Berdir, are you free to review this patch again?

Since the added code in #23 was minimal (barely adding another check on the existence of the function), I'll go ahead and commit these changes. Thanks to all who helped.

Thank you for your work on this much useful module! :)