I have just upgraded from 6.11.3 to 6.11.4
I do this manually using Filezilla and overwrite all downloaded files. I refreshed my site and usually I'm asked to upgrade but this time there was no such instruction. I had to manually go to the install folder and all went well.

No css3 errors on a) public access b) login page c) logged in users

using https://validator.w3.org/nu/?doc=
One html5 error only on login page which was addressed in an earlier post https://forums.b2evolution.net/html5-and-cssgbp-validation-of-6-10-6#c112266

Error: Attribute autocorrect not allowed on element input at this point.

From line 150, column 20; to line 150, column 213

s="input"><input type="text" value="" size="18" maxlength="255" name="x" class="input_text form_text_input form-control field_required" autocapitalize="off" autocorrect="off" id="x" required="required" />↩ <spa