From 103f51d867dc3966e44d79e949e78380efef5e2d Mon Sep 17 00:00:00 2001
From: Patrick Cloke <clokep@users.noreply.github.com>
Date: Wed, 20 Apr 2022 12:03:03 -0400
Subject: [PATCH] Fix Jinja templating error when generating thumbnail URLs.
 (#12510)

scale is meant to be a constant string, not refer to a variable.
---
 changelog.d/12510.bugfix         | 1 +
 synapse/res/templates/notif.html | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)
 create mode 100644 changelog.d/12510.bugfix

diff --git a/changelog.d/12510.bugfix b/changelog.d/12510.bugfix
new file mode 100644
index 0000000000..d5856e982a
--- /dev/null
+++ b/changelog.d/12510.bugfix
@@ -0,0 +1 @@
+Fix a long-standing bug where the image thumbanils embedded into email notifications were broken.
diff --git a/synapse/res/templates/notif.html b/synapse/res/templates/notif.html
index 0aaef97df8..7d86681fed 100644
--- a/synapse/res/templates/notif.html
+++ b/synapse/res/templates/notif.html
@@ -30,7 +30,7 @@
                     {%- elif message.msgtype == "m.notice" %}
                         {{ message.body_text_html }}
                     {%- elif message.msgtype == "m.image" and message.image_url %}
-                        <img src="{{ message.image_url|mxc_to_http(640, 480, scale) }}" />
+                        <img src="{{ message.image_url|mxc_to_http(640, 480, 'scale') }}" />
                     {%- elif message.msgtype == "m.file" %}
                         <span class="filename">{{ message.body_text_plain }}</span>
                     {%- else %}