diff --git a/pixelegg/css/mobile.css b/pixelegg/css/mobile.css
index 9f26988973..2b3fd6deea 100644
--- a/pixelegg/css/mobile.css
+++ b/pixelegg/css/mobile.css
@@ -3708,7 +3708,7 @@ td.lettersearch {
   background-color: #fafafa;
 }
 #egwpopup #egwpopup_list .egwpopup_message.egwpopup_expanded .egwpopup_message_inner_container {
-  height: auto;
+  height: calc(100% - 62px);
   overflow: auto;
 }
 #egwpopup #egwpopup_list .egwpopup_message.egwpopup_expanded .egwpopup_collapse {
diff --git a/pixelegg/css/pixelegg.css b/pixelegg/css/pixelegg.css
index 742b9820e8..44cb0de5d9 100644
--- a/pixelegg/css/pixelegg.css
+++ b/pixelegg/css/pixelegg.css
@@ -3689,7 +3689,7 @@ td.lettersearch {
   background-color: #fafafa;
 }
 #egwpopup #egwpopup_list .egwpopup_message.egwpopup_expanded .egwpopup_message_inner_container {
-  height: auto;
+  height: calc(100% - 62px);
   overflow: auto;
 }
 #egwpopup #egwpopup_list .egwpopup_message.egwpopup_expanded .egwpopup_collapse {
diff --git a/pixelegg/less/layout_messages.less b/pixelegg/less/layout_messages.less
index 5070f0be94..cd74f2aa61 100755
--- a/pixelegg/less/layout_messages.less
+++ b/pixelegg/less/layout_messages.less
@@ -152,7 +152,7 @@
 				background-color: #fafafa;
 			}
 			.egwpopup_message_inner_container {
-				height: auto;
+				height: ~"calc(100% - 62px)";
 				overflow: auto;
 			}
 			.egwpopup_collapse {
diff --git a/pixelegg/mobile/fw_mobile.css b/pixelegg/mobile/fw_mobile.css
index 0d11467b79..a3f86c1565 100644
--- a/pixelegg/mobile/fw_mobile.css
+++ b/pixelegg/mobile/fw_mobile.css
@@ -3719,7 +3719,7 @@ td.lettersearch {
   background-color: #fafafa;
 }
 #egwpopup #egwpopup_list .egwpopup_message.egwpopup_expanded .egwpopup_message_inner_container {
-  height: auto;
+  height: calc(100% - 62px);
   overflow: auto;
 }
 #egwpopup #egwpopup_list .egwpopup_message.egwpopup_expanded .egwpopup_collapse {