ModelAdmin scrollbar problem when actions=None

[zauddelig]

Having a class like this:

class MyModelAdmin(admin.ModelAdmin):
    actions = None

Will lead to a list view with single column table and an unexpected horizontal scrollbar.
The problem appears with Opera.

To my opinion the problem is with this line in django/contrib/admin/static/admin/css/changelists.css:

#changelist table tbody td:first-child, #changelist table tbody th:first-child {
    border-left: 0;
    border-right: 1px solid #ddd;
}

this not takes in consideration when we have th:first-child that is also a last-child the proposed solution is to add this rule:

#changelist table tbody th:first-child:last-child {
    border-right: 0;
}

pull request:
​https://github.com/django/django/pull/4849