From dead697600900eee40b460bade69aa66c620e8f5 Mon Sep 17 00:00:00 2001
From: js87zz <js87zz.lee@nhn.com>
Date: Fri, 6 Aug 2021 21:22:49 +0900
Subject: [PATCH 1/2] fix: add z-index: 100 to toastui-editor-contents for IE11

---
 apps/editor/src/css/contents.css | 1 +
 1 file changed, 1 insertion(+)

diff --git a/apps/editor/src/css/contents.css b/apps/editor/src/css/contents.css
index bd5964cbd7..a52ad2793a 100644
--- a/apps/editor/src/css/contents.css
+++ b/apps/editor/src/css/contents.css
@@ -36,6 +36,7 @@ table.ProseMirror-selectednode {
   font-size: 13px;
   font-family: 'Open Sans', 'Helvetica Neue', 'Helvetica', 'Arial', '나눔바른고딕',
     'Nanum Barun Gothic', '맑은고딕', 'Malgun Gothic', sans-serif;
+  z-index: 100;
 }
 
 .toastui-editor-contents *:not(table) {

From 3a45564b91ccfabda38a4f6e356b7e5fb0cfe38e Mon Sep 17 00:00:00 2001
From: js87zz <js87zz.lee@nhn.com>
Date: Tue, 10 Aug 2021 11:25:33 +0900
Subject: [PATCH 2/2] chore: apply code review

---
 apps/editor/src/css/contents.css                 | 10 ++++++++--
 apps/editor/src/css/editor.css                   | 13 ++++++-------
 plugins/code-syntax-highlight/src/css/plugin.css |  2 +-
 3 files changed, 15 insertions(+), 10 deletions(-)

diff --git a/apps/editor/src/css/contents.css b/apps/editor/src/css/contents.css
index a52ad2793a..c49dd91374 100644
--- a/apps/editor/src/css/contents.css
+++ b/apps/editor/src/css/contents.css
@@ -1,3 +1,9 @@
+/* 
+  z-index basis
+  -1: pseudo element
+  20 - preview, wysiwyg
+  30 - wysiwyg code block language editor, tooltip, popup, context menu
+*/
 .ProseMirror {
   font-family: 'Open Sans', 'Helvetica Neue', 'Helvetica', 'Arial', '나눔바른고딕',
     'Nanum Barun Gothic', '맑은고딕', 'Malgun Gothic', sans-serif;
@@ -36,7 +42,7 @@ table.ProseMirror-selectednode {
   font-size: 13px;
   font-family: 'Open Sans', 'Helvetica Neue', 'Helvetica', 'Arial', '나눔바른고딕',
     'Nanum Barun Gothic', '맑은고딕', 'Malgun Gothic', sans-serif;
-  z-index: 100;
+  z-index: 20;
 }
 
 .toastui-editor-contents *:not(table) {
@@ -425,7 +431,7 @@ table.ProseMirror-selectednode {
   border: 1px solid #ccc;
   border-radius: 2px;
   background-color: #fff;
-  z-index: 100;
+  z-index: 30;
 }
 
 .toastui-editor-ww-code-block-language input {
diff --git a/apps/editor/src/css/editor.css b/apps/editor/src/css/editor.css
index 3a6272dab4..c81b3b2e7c 100644
--- a/apps/editor/src/css/editor.css
+++ b/apps/editor/src/css/editor.css
@@ -118,7 +118,6 @@
 .toastui-editor-ww-container {
   display: none;
   overflow: hidden;
-  z-index: 10;
   height: inherit;
   background-color: #fff;
 }
@@ -144,7 +143,7 @@
 .toastui-editor-md-mode .toastui-editor-md-container,
 .toastui-editor-ww-mode .toastui-editor-ww-container {
   display: block;
-  z-index: 100;
+  z-index: 20;
 }
 
 .toastui-editor-md-mode .toastui-editor-md-vertical-style {
@@ -398,7 +397,7 @@
 .toastui-editor-dropdown-toolbar {
   position: absolute;
   height: 46px;
-  z-index: 101;
+  z-index: 30;
   border-radius: 2px;
   box-shadow: 0 2px 4px 0 rgba(0, 0, 0, 0.08);
   border: 1px solid #dadde6;
@@ -418,7 +417,7 @@
   width: 400px;
   margin-right: auto;
   background: #fff;
-  z-index: 9999;
+  z-index: 30;
   position: absolute;
   border-radius: 2px;
   box-shadow: 0 2px 4px 0 rgba(0, 0, 0, 0.08);
@@ -578,7 +577,7 @@
   left: 0;
   border: 1px solid #00a9ff;
   background: rgba(0, 169, 255, 0.1);
-  z-index: 999;
+  z-index: 30;
 }
 
 .toastui-editor-popup-add-table .toastui-editor-table-description {
@@ -654,7 +653,7 @@
   border-radius: 2px;
   box-shadow: 0 2px 4px 0 rgba(0, 0, 0, 0.08);
   border: 1px solid #dadde6;
-  z-index: 100;
+  z-index: 30;
   padding: 5px 0;
   background-color: #fff;
 }
@@ -748,7 +747,7 @@
 .toastui-editor-tooltip {
   position: absolute;
   background-color: #444;
-  z-index: 999;
+  z-index: 30;
   padding: 4px 7px;
   font-size: 12px;
   border-radius: 3px;
diff --git a/plugins/code-syntax-highlight/src/css/plugin.css b/plugins/code-syntax-highlight/src/css/plugin.css
index 049a1c53f3..728efd49ed 100644
--- a/plugins/code-syntax-highlight/src/css/plugin.css
+++ b/plugins/code-syntax-highlight/src/css/plugin.css
@@ -31,7 +31,7 @@ pre[class*="language-"] {
   position: fixed;
   display: inline-block;
   right: 35px;
-  z-index: 100;
+  z-index: 30;
 }
 
 .toastui-editor-code-block-language-input {