From 312e5e0745c54b72b8b0141b8db1b69f5319afe8 Mon Sep 17 00:00:00 2001
From: Joey Wunderlich <joey.wunderlich@gmail.com>
Date: Thu, 10 Nov 2022 12:15:21 -0800
Subject: [PATCH] don't duplicate persistent share links when importing

---
 webapp/src/app.tsx | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/webapp/src/app.tsx b/webapp/src/app.tsx
index f27249643ed8..b5eafcce47c8 100644
--- a/webapp/src/app.tsx
+++ b/webapp/src/app.tsx
@@ -5387,9 +5387,18 @@ async function importGithubProject(repoid: string, requireSignin?: boolean) {
 
 function loadHeaderBySharedId(id: string) {
     core.showLoading("loadingheader", lf("loading project..."));
+    let previousHeader: pxt.workspace.Header;
+    if (id.startsWith("S") && auth.hasIdentity() && data.getData<string>(auth.LOGGED_IN)) {
+        // if loading a persistent url, check for existing headers
+        previousHeader = workspace.getHeaders().find(h => h.pubPermalink === id);
+    }
+
+    const projHeaderPromise = previousHeader
+        ? Promise.resolve(previousHeader)
+        : workspace.installByIdAsync(id);
 
-    workspace.installByIdAsync(id)
-        .then(hd => theEditor.loadHeaderAsync(hd, null))
+    projHeaderPromise
+        .then(hd => theEditor.loadHeaderAsync(hd, null, !!previousHeader))
         .catch(e => {
             theEditor.openHome();
             core.handleNetworkError(e);