In our Phorge instance, we end up with inconsistency in milestone descriptions, as it is cumbersome to manually open and copy the previous milestone's description.
Currently you have to:
1. Click "Previous Milestone" to open in a new tab
2. Click "Edit Details" to be able to copy any potential markiup (for example a `#link` to another project)
3. Mark all text
4. Copy it
5. Switch back to the previous tab
6. Paste the description of the previous milestone and edit it
Thus the goal is to reduce the number of steps.
Upstreaming from https://phabricator.wikimedia.org/T371449 as I assume that other stakeholders might be interested too in streamlining workflows.
Outdated screenshot when it comes to the exact strings, but gives you an idea:
{F2950878}