From 436ed8b8c212a44f560742252d9253b8cf70d5f3 Mon Sep 17 00:00:00 2001
From: Netanel Haber <58652339+netanel-haber@users.noreply.github.com>
Date: Fri, 17 Nov 2023 10:58:10 +0200
Subject: [PATCH] Fixed instant loading indicator in Chrome when serving
 gzipped (#6322)

* bypass chrome event.total 0 when content gzipped by getting total off of Content-Length header

* styling; NaN should be replaced with 0 as well, so no nullish coalescing won't work
---
 src/templates/assets/javascripts/browser/request/index.ts | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/templates/assets/javascripts/browser/request/index.ts b/src/templates/assets/javascripts/browser/request/index.ts
index 74a56a64d..3c050f9b8 100644
--- a/src/templates/assets/javascripts/browser/request/index.ts
+++ b/src/templates/assets/javascripts/browser/request/index.ts
@@ -85,7 +85,12 @@ export function request(
     // Handle download progress
     if (typeof options?.progress$ !== "undefined") {
       req.addEventListener("progress", event => {
-        options.progress$!.next((event.loaded / event.total) * 100)
+        if (event.lengthComputable) {
+          options.progress$!.next((event.loaded / event.total) * 100)
+        } else { // https://bugs.chromium.org/p/chromium/issues/detail?id=463622
+          const totalFromHeader = Number(req.getResponseHeader("Content-Length")) || 0
+          options.progress$!.next((event.loaded / totalFromHeader) * 100)
+        }
       })
 
       // Immediately set progress to 5% to indicate that we're loading