ID:2525471
 
Resolved
Undoing an icon edit that was done on a different frame than the one currently selected could sometimes result in the undo icon being loaded into the wrong frame.
BYOND Version:512
Operating System:Windows 7 Pro
Web Browser:Firefox 56.0
Applies to:Dream Maker
Status: Resolved (513.1502)

This issue has been resolved.
I've finally managed to replicate this annoying bug. Like http://www.byond.com/forum/post/2525288, it happens since the new icon editor was added.

Descriptive Problem Summary:
Image editor corrupts icons when using Undo and Select tool.

Numbered Steps to Reproduce Problem:
1. Create an icon with 4 dirs.
2. Switch to EAST direction.
4. Select a part of icon and delete it.
5. Select another part of icon.
6. Switch to NORTH direction.
7. Press CTRL+Z to Undo.

Expected results:
Editor switches to EAST and Undos.
Actual results:
Editor switches to SOUTH. The SOUTH icon state is replaced with EAST icon.
Quick question here: When you say "select a part of icon" do you mean using the selection tool to only select part of an individual frame?
Right, I'm selecting and deleting a random piece of a frame.
Lummox JR resolved issue with message:
Undoing an icon edit that was done on a different frame than the one currently selected could sometimes result in the undo icon being loaded into the wrong frame.