Scroll in popover: max 10 items shown and no flex shrink

Signed-off-by: John Molakvoæ (skjnldsv) <skjnldsv@protonmail.com>

core/css/apps.scss

@@ -822,6 +822,7 @@ kbd {
 	}
 	li {
 		display: flex;
+		flex: 0 0 auto;
 		> button,
 		> a,
 		> .menuitem {

core/css/styles.scss

@@ -1410,6 +1410,10 @@ div.crumb {
 		.popovermenu {
 			top: 100%;
 			margin-right: 3px;
+			ul {
+				max-height: 345px;
+				overflow-y: scroll;
+			}
 			.in-breadcrumb {
 				display: none;
 			}