diff --git a/dlls/mshtml/htmldoc.c b/dlls/mshtml/htmldoc.c
index 7168bab7643..36308f08d8d 100644
--- a/dlls/mshtml/htmldoc.c
+++ b/dlls/mshtml/htmldoc.c
@@ -413,8 +413,23 @@ static HRESULT WINAPI HTMLDocument_get_scripts(IHTMLDocument2 *iface, IHTMLEleme
static HRESULT WINAPI HTMLDocument_put_designMode(IHTMLDocument2 *iface, BSTR v)
{
HTMLDocument *This = impl_from_IHTMLDocument2(iface);
- FIXME("(%p)->(%s)\n", This, debugstr_w(v));
- return E_NOTIMPL;
+ HRESULT hres;
+
+ static const WCHAR onW[] = {'o','n',0};
+
+ TRACE("(%p)->(%s)\n", This, debugstr_w(v));
+
+ if(strcmpiW(v, onW)) {
+ FIXME("Unsupported arg %s\n", debugstr_w(v));
+ return E_NOTIMPL;
+ }
+
+ hres = setup_edit_mode(This->doc_obj);
+ if(FAILED(hres))
+ return hres;
+
+ call_property_onchanged(&This->cp_container, 1014);
+ return S_OK;
}
static HRESULT WINAPI HTMLDocument_get_designMode(IHTMLDocument2 *iface, BSTR *p)