Feedback: variables render differently in Insiders

[mrleemurray]

Testing: #244445

Snippet:

#app {
		box-sizing: border-box;
		margin: 0 auto;
		display: flex;
		flex-direction: column;
		height: 100%;
		background-color: var(--figma-color-bg);
		color: var(--figma-color-text);
 }

Insiders:

Stable:

Theme: Dark+