Redmine

We just installed the 4.0.0 Version of Redmine and came across the following bug:
Our Avatar images at journal entries have a big offset and appear nearly outside the page (see attached image: redmine_css_bug.PNG).

We identified (Browser dev tools) the css-source of the offset as the application.css (the one outside the custom themes) and the following lines:

...
body.avatars-on div.journal {padding-left:32px;}
div.journal h4 img.gravatar {margin-left:-32px;}
...

We tried enabling the gravatar setting at Administration > Configuration > Display and the offset disappeared.

We experienced this on the following environment:

Environment:
> Redmine version                4.0.0.stable
> Ruby version                   2.4.4-p296 (2018-03-28) [x86_64-linux]
> Rails version                  5.2.2
> Environment                    production
> Database adapter               Mysql2
> Mailer queue                   ActiveJob::QueueAdapters::AsyncAdapter
> Mailer delivery                smtp
SCM:
> Git                            1.9.1
> Filesystem                     
Redmine plugins:
> redmine_checklists             3.1.14
> redmine_contacts               4.2.3
> redmine_people                 1.4.0