diff --git a/src/Tinter.js b/src/Tinter.js
index f2a02b6e6d..b4a624e0ad 100644
--- a/src/Tinter.js
+++ b/src/Tinter.js
@@ -224,6 +224,7 @@ class Tinter {
     }
 
     setTheme(theme) { 
+        console.trace("setTheme " + theme);
         this.theme = theme;
 
         // update keyRgb from the current theme CSS itself, if it defines it
@@ -301,6 +302,8 @@ class Tinter {
             if (ss.disabled) continue;
             if (!ss.cssRules) continue;
 
+            if (DEBUG) console.debug("calcCssFixups checking " + ss.cssRules.length + " rules for " + ss.href);
+
             for (let j = 0; j < ss.cssRules.length; j++) {
                 const rule = ss.cssRules[j];
                 if (!rule.style) continue;
diff --git a/src/components/structures/MatrixChat.js b/src/components/structures/MatrixChat.js
index 7847e8e8dc..183db8a756 100644
--- a/src/components/structures/MatrixChat.js
+++ b/src/components/structures/MatrixChat.js
@@ -922,6 +922,11 @@ module.exports = React.createClass({
         styleElements[theme].disabled = false;
 
         const switchTheme = function() {
+            // we re-enable our theme here just in case we raced with another
+            // theme set request as per https://github.com/vector-im/riot-web/issues/5601.
+            // We could alternatively lock or similar to stop the race, but
+            // this is probably good enough for now.
+            styleElements[theme].disabled = false;
             Object.values(styleElements).forEach((a) => {
                 if (a == styleElements[theme]) return;
                 a.disabled = true;