Icon Element Monochrome Checkbox Doesn't Work

[hawkerm]

Describe the bug
The IconElement sample's first example has a Monochrome checkbox, it doesn't change anything in the sample and still shows the blue slices (see image below).

Steps to reproduce the bug

1. Go to IconElement sample
2. Click on 'Monochrome' checkbox

Expected behavior
Should make image monochrome

Actual behavior
Nothing changes

Screenshots

Version Info

• App downloaded from Store
  • If so, which version? 1.2.19.0
• App built locally from source
  • If so, which branch? (WinUI 3 versions are built off the winui3preview branch)

Additional context

Windows 10 version:

• Insider Build (xxxxx)
• May 2020 Update (19041)
• November 2019 Update (18363)
• May 2019 Update (18362)
• October 2018 Update (17763)
• April 2018 Update (17134)
• Fall Creators Update (16299)
• Creators Update (15063)
• Anniversary Update (14393)

Device form factor:

• Desktop
• Mobile
• Xbox
• Surface Hub
• IoT