Scroll cell into view major update:

We change `scrollTop` to scroll cells into view, but cell's position
is based on template height, which is not correct. Markdown cells
are dynamic, so after we scroll cells into view, they will change
their real height, thus we need to set `scrollTop` again to adjust
the position again.

For code cell, they will call `updateElementHeight` to change its
size. It should pass in `focusedElement` as the anchor element,
then the focused element will keep its visual position.

src/vs/workbench/contrib/notebook/browser/view/notebookCellList.ts

@@ -261,7 +261,14 @@ export class NotebookCellList extends WorkbenchList<CellViewModel> implements ID
 		const element = this.view.element(index);
 
 		if (viewItemOffset < scrollTop || viewItemOffset > wrapperBottom) {
+			// let it render
 			this.view.setScrollTop(viewItemOffset - this.view.renderHeight / 2);
+
+			// after rendering, it might be pushed down due to markdown cell dynamic height
+			const elementTop = this.view.elementTop(index);
+			this.view.setScrollTop(elementTop - this.view.renderHeight / 2);
+
+			// reveal editor
 			if (!element.editorAttached) {
 				getEditorAttachedPromise(element).then(() => reveal(index, range, revealType));
 			} else {
@@ -295,15 +302,14 @@ export class NotebookCellList extends WorkbenchList<CellViewModel> implements ID
 			return;
 		}
 
-		let viewItemOffset = elementTop;
-
-		if (revealPosition === CellRevealPosition.Top) {
-			viewItemOffset = elementTop;
-		} else if (revealPosition === CellRevealPosition.Center) {
-			viewItemOffset = elementTop - this.view.renderHeight / 2;
-		}
-
+		// first render
+		const viewItemOffset = revealPosition === CellRevealPosition.Top ? elementTop : (elementTop - this.view.renderHeight / 2);
 		this.view.setScrollTop(viewItemOffset);
+
+		// second scroll as markdown cell is dynamic
+		const newElementTop = this.view.elementTop(index);
+		const newViewItemOffset = revealPosition === CellRevealPosition.Top ? newElementTop : (newElementTop - this.view.renderHeight / 2);
+		this.view.setScrollTop(newViewItemOffset);
 	}
 
 	revealInView(index: number) {