From a39dd64c5ebece50b0ae3574a5bb44885b99cefd Mon Sep 17 00:00:00 2001
From: toofar <toofar@spalge.com>
Date: Mon, 27 Nov 2023 08:16:34 +1300
Subject: Move pdf.js fetch() disabler earlier in the file.

We are setting window.Response to undefined to cause certain versions of
pdf.js to detect that fetch() isn't available and to fall back to XHRs. In
more recent versions of pdf.js the HTML string we were matching against has
changed, it has a 'type="module"' attribute now, so we need to change the
pattern we match against.

I don't think it matters where we put this mocking though, so I've just put it
after '<head>', which should hopefully be less fragile than matching against a
'<script>' element.

Note that this workaround isn't even relevant for the latest versions of
pdf.js (4+). It doesn't seem to use a check on `window.Response` as part of
fetch feature detection anymore (instead it uses fetch() for https? urls and
XHR otherwise). But I figured it was better to have the workaround applying
consistently, and not having an effect, vs having the workaround silently fail
to apply. Don't have a strong opinion on it though.

The other way to fix this would have been something like:

    attrs = ""
    if pdfjs_name.endswith(".mjs"):
        attrs = ' type="module"'
    pdfjs_script = f'<script src="../build/{html.escape(pdfjs_name)}"{attrs}></script>'
---
 qutebrowser/browser/pdfjs.py | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/qutebrowser/browser/pdfjs.py b/qutebrowser/browser/pdfjs.py
index 427ef4537..1a13f5bda 100644
--- a/qutebrowser/browser/pdfjs.py
+++ b/qutebrowser/browser/pdfjs.py
@@ -63,11 +63,11 @@ def generate_pdfjs_page(filename, url):
     viewhtml = viewhtml.replace('</body>',
                         '</body><script>{}</script>'.format(script))
     # WORKAROUND for the fact that PDF.js tries to use the Fetch API even with
-    # qute:// URLs.
-    pdfjs_script = f'<script src="../build/{html.escape(pdfjs_name)}"></script>'
-    viewhtml = viewhtml.replace(pdfjs_script,
-                        '<script>window.Response = undefined;</script>\n' +
-                        pdfjs_script)
+    # qute:// URLs, this is probably no longer needed in PDFjs 4+. See #4235
+    viewhtml = viewhtml.replace(
+        '<head>',
+        '<head>\n<script>window.Response = undefined;</script>\n'
+    )
     return viewhtml
 
 
-- 
cgit v1.2.3-54-g00ecf

