diff --git a/Userland/Libraries/LibWeb/HTML/AttributeNames.h b/Userland/Libraries/LibWeb/HTML/AttributeNames.h
index e931d47b4b3..746e40a0d3c 100644
--- a/Userland/Libraries/LibWeb/HTML/AttributeNames.h
+++ b/Userland/Libraries/LibWeb/HTML/AttributeNames.h
@@ -105,6 +105,7 @@ namespace AttributeNames {
     __ENUMERATE_HTML_ATTRIBUTE(longdesc)                   \
     __ENUMERATE_HTML_ATTRIBUTE(loop)                       \
     __ENUMERATE_HTML_ATTRIBUTE(low)                        \
+    __ENUMERATE_HTML_ATTRIBUTE(lowsrc)                     \
     __ENUMERATE_HTML_ATTRIBUTE(marginheight)               \
     __ENUMERATE_HTML_ATTRIBUTE(marginwidth)                \
     __ENUMERATE_HTML_ATTRIBUTE(max)                        \
diff --git a/Userland/Libraries/LibWeb/HTML/HTMLImageElement.idl b/Userland/Libraries/LibWeb/HTML/HTMLImageElement.idl
index d903faebc4a..660920d6f4f 100644
--- a/Userland/Libraries/LibWeb/HTML/HTMLImageElement.idl
+++ b/Userland/Libraries/LibWeb/HTML/HTMLImageElement.idl
@@ -30,7 +30,7 @@ interface HTMLImageElement : HTMLElement {
 
     // Obsolete
     [CEReactions, Reflect] attribute DOMString name;
-    [FIXME, CEReactions] attribute USVString lowsrc;
+    [CEReactions, Reflect] attribute USVString lowsrc;
     [CEReactions, Reflect] attribute DOMString align;
     [CEReactions, Reflect] attribute unsigned long hspace;
     [CEReactions, Reflect] attribute unsigned long vspace;