diff --git a/src/ide/views/asseteditor.ts b/src/ide/views/asseteditor.ts
index 2c94c83d..1e76c2e6 100644
--- a/src/ide/views/asseteditor.ts
+++ b/src/ide/views/asseteditor.ts
@@ -477,7 +477,9 @@ export class AssetEditorView implements ProjectView, pixed.EditorContext {
   setVisible?(showing: boolean): void {
     // TODO: make into toolbar?
     if (showing) {
-      // limit undo/redo to since opening this editor
+      // ensure asset editor is safe to perform synchronous reads/writes
+      projectWindows.flushAllWindows();
+      // limit undo/redo to since opening this asset editor
       projectWindows.undofiles = [];
       projectWindows.redofiles = [];
       if (Mousetrap.bind) {
diff --git a/src/ide/views/baseviews.ts b/src/ide/views/baseviews.ts
index 27e84264..13f2fa79 100644
--- a/src/ide/views/baseviews.ts
+++ b/src/ide/views/baseviews.ts
@@ -20,6 +20,7 @@ export interface ProjectView {
     recreateOnResize?: boolean;
     undoStep?(): void;
     redoStep?(): void;
+    flushChanges?(): void;
     replaceTextRange?(from: number, to: number, text: string): void;
 };
 
diff --git a/src/ide/views/editors.ts b/src/ide/views/editors.ts
index cecd5394..41fcc7ab 100644
--- a/src/ide/views/editors.ts
+++ b/src/ide/views/editors.ts
@@ -282,6 +282,14 @@ export class SourceEditor implements ProjectView {
     }, this.refreshDelayMsec);
   }
 
+  flushChanges() {
+    if (this.updateTimer) {
+      clearTimeout(this.updateTimer);
+      this.updateTimer = null;
+      current_project.updateFile(this.path, this.editor.state.doc.toString());
+    }
+  }
+
   inspectUnderCursor(update: ViewUpdate) {
     // TODO: handle multi-select
     const range = update.state.selection.main;
diff --git a/src/ide/windows.ts b/src/ide/windows.ts
index 07a80037..cffdc140 100644
--- a/src/ide/windows.ts
+++ b/src/ide/windows.ts
@@ -208,6 +208,15 @@ export class ProjectWindows {
     bootbox.alert(msg, () => { this.alerting = false; });
   }
 
+  flushAllWindows() {
+    for (var fileid in this.id2window) {
+      var wnd = this.id2window[fileid];
+      if (wnd && wnd.flushChanges) {
+        wnd.flushChanges();
+      }
+    }
+  }
+
   updateAllOpenWindows(store) {
     for (var fileid in this.id2window) {
       var wnd = this.id2window[fileid];