diff --git a/Dockerfile b/Dockerfile
index 3f8a7ac5bb..a49d5442de 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -2,8 +2,8 @@ FROM sitespeedio/webbrowsers:chrome-131.0-firefox-133.0-edge-131.0
 
 ARG TARGETPLATFORM=linux/amd64
 
-ENV SITESPEED_IO_BROWSERTIME__XVFB true
-ENV SITESPEED_IO_BROWSERTIME__DOCKER true
+ENV SITESPEED_IO_BROWSERTIME__XVFB=true
+ENV SITESPEED_IO_BROWSERTIME__DOCKER=true
 
 COPY docker/webpagereplay/$TARGETPLATFORM/wpr /usr/local/bin/
 COPY docker/webpagereplay/wpr_cert.pem /webpagereplay/certs/