Adding issue for zero monitor representation.

xrdp/xrdp_egfx.c

@@ -678,6 +678,19 @@ xrdp_egfx_reset_graphics(struct xrdp_egfx_bulk *bulk, int width, int height,
     out_uint32_le(s, 340); /* pduLength */
     out_uint32_le(s, width);
     out_uint32_le(s, height);
+    /*
+        TODO: Fix hack where working around 0 monitors is necessary.
+
+        In cases where multi-mon is not used for XRDP, internally 0 monitors
+        are represented, even though we implicitly have one: The entire session!
+
+        Some Microsoft clients (Mainly the Mac OS one) require that at least
+        one monitor be transmitted for EGFX to function, which is why this
+        change was necessary.
+
+        See https://github.com/neutrinolabs/xrdp/pull/2338#discussion_r944685856
+        https://github.com/neutrinolabs/xrdp/issues/2503
+    */
     out_uint32_le(s, monitor_count == 0 ? 1 : monitor_count);
     if (monitor_count == 0)
     {
@@ -870,7 +883,7 @@ xrdp_egfx_process(struct xrdp_egfx *egfx, struct stream *s)
                 break;
             case XR_RDPGFX_CMDID_QOEFRAMEACKNOWLEDGE:
                 break;
-            /* 
+            /*
                TODO: Handle Cache Import PDU here.
                https://github.com/neutrinolabs/xrdp/issues/2502
                case XR_RDPGFX_CMDID_CACHEIMPORTOFFER: