Fix tab border and focus outline (#239907)

* fix tab border color and focus outline

* 💄

Author: benibenj

src/vs/workbench/browser/parts/editor/media/multieditortabscontrol.css

@@ -50,7 +50,7 @@
 	display: none;
 }
 
-.monaco-workbench .part.editor > .content .editor-group-container > .title .tab:not(.active) .tabs-and-actions-container.tabs-border-bottom::after {
+.monaco-workbench .part.editor > .content .editor-group-container > .title > .tabs-and-actions-container.tabs-border-bottom::after {
 	content: '';
 	position: absolute;
 	bottom: 0;
@@ -293,13 +293,17 @@
 	background-color: var(--tab-border-top-color);
 }
 
-.monaco-workbench .part.editor > .content .editor-group-container > .title .tabs-container > .tab.active.tab-border-bottom:not(:focus) > .tab-border-bottom-container {
+.monaco-workbench .part.editor > .content .editor-group-container > .title .tabs-container > .tab.active.tab-border-bottom > .tab-border-bottom-container {
 	z-index: 10;
 	bottom: 0;
 	height: 1px;
 	background-color: var(--tab-border-bottom-color);
 }
 
+.monaco-workbench .part.editor > .content .editor-group-container > .title .tabs-container > .tab.active.tab-border-bottom:focus > .tab-border-bottom-container {
+	background-color: var(--vscode-focusBorder);
+}
+
 .monaco-workbench .part.editor > .content .editor-group-container > .title .tabs-container > .tab.dirty-border-top:not(:focus) > .tab-border-top-container {
 	z-index: 6;
 	top: 0;