Fixes #86696: Tweak hit testing on Firefox for pseudo elements

src/vs/editor/browser/controller/mouseTarget.ts

@@ -925,6 +925,23 @@ export class MouseTargetFactory {
 			}
 		}
 
+		// For inline decorations, Gecko returns the `<span>` of the line and the offset is the `<span>` with the inline decoration
+		if (hitResult.offsetNode.nodeType === hitResult.offsetNode.ELEMENT_NODE) {
+			const parent1 = hitResult.offsetNode.parentNode; // expected to be the view line div
+			const parent1ClassName = parent1 && parent1.nodeType === parent1.ELEMENT_NODE ? (<HTMLElement>parent1).className : null;
+
+			if (parent1ClassName === ViewLine.CLASS_NAME) {
+				const tokenSpan = hitResult.offsetNode.childNodes[Math.min(hitResult.offset, hitResult.offsetNode.childNodes.length - 1)];
+				if (tokenSpan) {
+					const p = ctx.getPositionFromDOMInfo(<HTMLElement>tokenSpan, 0);
+					return {
+						position: p,
+						hitTarget: null
+					};
+				}
+			}
+		}
+
 		return {
 			position: null,
 			hitTarget: <HTMLElement>hitResult.offsetNode