strip out unneeded -ms- prefixes

src/skins/vector/css/vector-web/structures/_LeftPanel.scss

@@ -17,7 +17,6 @@ limitations under the License.
 .mx_LeftPanel {
     position: relative;
 
-    display: -ms-flexbox;
     display: flex;
     flex-direction: column;
 }
@@ -35,7 +34,6 @@ limitations under the License.
 }
 
 .mx_LeftPanel .mx_RoomList_scrollbar {
-    -ms-flex-order: 1;
     order: 1;
 
     flex: 1 1 0;
@@ -49,7 +47,6 @@ limitations under the License.
 }
 
 .mx_LeftPanel .mx_BottomLeftMenu {
-    -ms-flex-order: 3;
     order: 3;
 
     border-top: 1px solid rgba(118, 207, 166, 0.2);

src/skins/vector/css/vector-web/structures/_RightPanel.scss

@@ -17,13 +17,11 @@ limitations under the License.
 .mx_RightPanel {
     position: relative;
 
-    display: -ms-flexbox;
     display: flex;
     flex-direction: column;
 }
 
 .mx_RightPanel_header {
-    -ms-flex-order: 1;
     order: 1;
 
     border-bottom: 1px solid $primary-hairline-color;
@@ -73,13 +71,11 @@ limitations under the License.
 .mx_RightPanel .mx_MemberList,
 .mx_RightPanel .mx_MemberInfo,
 .mx_RightPanel_blank {
-    -ms-flex-order: 2;
     order: 2;
     flex: 1 1 0;
 }
 
 .mx_RightPanel_footer {
-    -ms-flex-order: 3;
     order: 3;
 
     border-top: 1px solid $primary-hairline-color;

src/skins/vector/css/vector-web/structures/_RoomDirectory.scss

@@ -22,7 +22,6 @@ limitations under the License.
     margin-bottom: 12px;
     color: $primary-fg-color;
 
-    display: -ms-flexbox;
     display: flex;
 
     flex-direction: column;
@@ -31,7 +30,6 @@ limitations under the License.
 .mx_RoomDirectory_list {
     flex: 1;
 
-    display: -ms-flexbox;
     display: flex;
 
     flex-direction: column;

src/skins/vector/css/vector-web/views/globals/_GuestWarningBar.scss

@@ -18,7 +18,6 @@ limitations under the License.
     background-color: $accent-color;
     color: $accent-fg-color;
 
-    display: -ms-flexbox;
     display: flex;
     align-items: center;
 }

src/skins/vector/css/vector-web/views/globals/_MatrixToolbar.scss

@@ -18,7 +18,6 @@ limitations under the License.
     background-color: $accent-color;
     color: $accent-fg-color;
 
-    display: -ms-flexbox;
     display: flex;
     align-items: center;
 }