Describe the bug

It seems like the blank-color property does not fill b-img-lazy with a desired color on Firefox if an image is initially visible and its svg placeholder is not cached. This bug does not occur to elements outside of the viewport and on Chromium entirely.

Steps to reproduce the bug

1. Launch the latest Firefox browser
2. Go to https://codesandbox.io/s/inspiring-murdock-uqic0
3. Wait for images to start loading
4. See error

Expected behavior

All images should have a red background set by the blank-color="red" prop while loading.

Versions

Libraries:

• BootstrapVue: 2.21.2
• Bootstrap: 4.5.3
• Vue: 2.6.12

Environment:

• OS: Windows 10
• Browser: Firefox 84.0.2

Additional context

The screenshot illustrating the issue: