Make sure every editor resize event has a measure scheduled after it

src/docview.ts

@@ -59,7 +59,7 @@ export class DocView extends ContentView {
   // position, if we know the editor is going to scroll that position
   // into view.
   update(update: ViewUpdate) {
-    this.lastUpdate = Date.now()
+    if (update.transactions.length) this.lastUpdate = Date.now()
     let changedRanges = update.changedRanges
     if (this.minWidth > 0 && changedRanges.length) {
       if (!changedRanges.every(({fromA, toA}) => toA < this.minWidthFrom || fromA > this.minWidthTo)) {

src/domobserver.ts

@@ -24,6 +24,7 @@ export class DOMObserver {
   ignoreSelection: DOMSelection = new DOMSelection
 
   delayedFlush = -1
+  resizeTimeout = -1
   queue: MutationRecord[] = []
   lastFlush = 0
 
@@ -77,7 +78,11 @@ export class DOMObserver {
     this.onSelectionChange = this.onSelectionChange.bind(this)
     if (typeof ResizeObserver == "function") {
       this.resize = new ResizeObserver(() => {
-        if (this.view.docView.lastUpdate < Date.now() - 100) this.view.requestMeasure()
+        if (this.view.docView.lastUpdate < Date.now() - 50 && this.resizeTimeout < 0)
+          this.resizeTimeout = setTimeout(() => {
+            this.resizeTimeout = -1
+            this.view.requestMeasure()
+          }, 50)
       })
       this.resize.observe(view.scrollDOM)
     }
@@ -295,6 +300,7 @@ export class DOMObserver {
     for (let dom of this.scrollTargets) dom.removeEventListener("scroll", this.onScroll)
     window.removeEventListener("scroll", this.onScroll)
     clearTimeout(this.parentCheck)
+    clearTimeout(this.resizeTimeout)
   }
 }