Describe the bug

A clear and concise description of what the bug is.

Steps to reproduce the bug

1. Set up a custom theme, as described here (https://bootstrap-vue.org/docs/reference/theming)
2. Before the imports, set the $input-color variable.
3. Use the b-form-tags element
4. Type in the input portion of the element; it does not respect the $input-color variable.

Expected behavior

The typed text should appear in the $input-color variable

Versions

Libraries:

• BootstrapVue: 2.21.2
• Bootstrap: 4.5.3
• Vue: 2.6.11

Environment:

• Device: Any
• OS: Any
• Browser: Any
• Version: Any

Demo link

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Additional context

Add any other context about the bug here.