CSS classes configuration form field

#2 works for me. Moving to RTBC

A couple of nitpicks with patch #2:

1. +++ b/config/schema/manage_display.schema.yml
   @@ -4,6 +4,9 @@ field.formatter.settings.title:
   +    tag_css_classes:
   

   I don't think this new setting name needs the tag_ prefix.

2. +++ b/src/Plugin/Field/FieldFormatter/TitleFormatter.php
   @@ -70,7 +79,8 @@ class TitleFormatter extends StringFormatter {
   +      $item['#prefix'] = ($tag_css_classes !== '') ? "<$tag class='$tag_css_classes'>" : "<$tag>";
   

   Would probably be better to use !empty() here.

Updated patch that addresses items in #6.

Created a new MR.

Added changes as a mr and updated the settingsSummary() method in order not to show the summary for classes if the field is empty.

Thanks for the contributions. For sure I can see that some sites would wish for this feature I even have a feeling that someone requested it before although I can't find the issue now.

This module aims to get the formatters added to Drupal Core. When developing the formatters I aimed to copy the Core formatters as closely as possible. Core mostly doesn't add a lot of extra configuration options, so I expect they wouldn't accept the option in this feature request. Hence it seems like we shouldn't add it here. What does anyone else think?

Perhaps can use this https://www.drupal.org/project/field_formatter_class → ?

Merged the MR for adding CSSS class to the title.
thanks all

OK, but in #11 I said "Core mostly doesn't add a lot of extra configuration options, so I expect they wouldn't accept the option in this feature request. Hence it seems like we shouldn't add it here." 😃

There is a Core issue ✨ Add a Title Formatter Active that seems quite close to commit now. We would then remove the TitleFormatter from this module, with an update hook to fix existing sites. At this point classes would be lost on any site that had used them. So I feel we should revert this change to avoid confusion.

Does that make sense??

thanks @adamps

I reverted all my changes. let's wait for the Drupal update.

Great thanks. To help future readers, I feel it's better to make it clear that we won't fix it here.

If you have enthusiasm for improving this module, then a really useful job would be to review the core issue and help get it in. The eventual goal for this module is to make it obsolete😃.