Updates scrollbar styles

- separates scrollbar fix in scss to its own mixin
- adds preload selector in scrollbar styles in web components

Author: d13

src/webviews/apps/shared/components/styles/lit/base.css.ts

@@ -61,4 +61,8 @@ export const scrollableBase = css`
 		border-color: var(--vscode-scrollbarSlider-background);
 		transition: none;
 	}
+
+	:host-context(.preload) .scrollable {
+		transition: none;
+	}
 `;

src/webviews/apps/shared/styles/scrollbars.scss

@@ -1,10 +1,14 @@
-@mixin scrollableBase() {
+@mixin scrollbarFix() {
 	// This @supports selector is a temporary fix for https://github.com/microsoft/vscode/issues/213045#issuecomment-2211442905
 	@supports selector(::-webkit-scrollbar) {
 		html {
 			scrollbar-color: unset;
 		}
 	}
+}
+
+@mixin scrollableBase() {
+	@include scrollbarFix();
 
 	body {
 		&.scrollable,