Add a note so future maintainers (myself included) know what's going on with the timestamp comparison

1 files changed, 6 insertions, 0 deletions

diff --git a/src/greeterbackground.c b/src/greeterbackground.c
index b76786f..4dd4fa7 100644
--- a/src/greeterbackground.c
+++ b/src/greeterbackground.c
@@ -735,6 +735,12 @@ greeter_background_set_active_monitor(GreeterBackground* background,
     if (priv->active_monitor_change_in_progress)
         return;
 
+    /* Prevents infinite signal emmission between two monitors (LP: #1410406, #1509780)
+     * There are some rare scenarios when using multiple monitors that cause the greeter
+     * to switch back and forth between the monitors indefinitely. By comparing the
+     * timestamp at this precision (1/10th of a second), this should no longer be
+     * possible.
+     */
     timestamp = floor(g_get_monotonic_time () * 0.00001);
     if (timestamp == priv->active_monitor_change_last_timestamp)
         return;