Duplicate Upgrading Barracks shows "idle" state graphics

[Elevenar]

Game version: v1.15.6-(2892adf) (2016-09-21 7:40)
Game world: BETA 1
Browser + version: Version 53.0.2785.116 m
Flash Player version: You have version 23,0,0,162 installed
Operating System: Windows 10 Pro Insider Preview
Screen resolution: 1920 x 1080
Account name: Elevenar
Humans or Elves: Humans for sure

Reproducibility: 5/5

Current situation:
Upgrading Barracks from Level 19 to 20 shows the idle state graphics, right after starting the upgrade. Reloading the game removes it.

Expected situation:
Upgrading buildings should not show idle state graphics, not even without reloading.

Screenshot:

 

[DeletedUser1178]

I've had the same thing, upgrading Gem Manufactories, since the last upgrade.

 

[Muf-Muf]

Thanks for the report. This happens with several buildings and is a known issue.