Option to Expand All by default in diffs

Description

Reviewing large code changes with many files is made difficult when the web interface selects some file changes to be collapsed by default (I'm presuming based on size). This makes it easy to miss and/or pass over these changes. From a code review/approval point of view, this is dangerous.

Proposal

Add a setting to allow users to set Expand All by default.

Current Workaround

Currently I execute this on diff load;

$(".fa-caret-right").click()