fixed box-shadow display while fully collapsed sidebar

build/scss/_layout.scss

@@ -493,6 +493,13 @@ body:not(.sidebar-mini-md) {
     width: $sidebar-width;
   }
 
+  .sidebar-collapse:not(.sidebar-mini):not(.sidebar-mini-md) & {
+    &,
+    &::before {
+      box-shadow: none !important;
+    }
+  }
+
   .sidebar-collapse & {
     &,
     &::before {

build/scss/_sidebar-mini.scss

@@ -44,12 +44,22 @@
     @include sidebar-mini-breakpoint;
   }
 }
+@include media-breakpoint-down(md) {
+  .sidebar-mini.sidebar-collapse .main-sidebar {
+    box-shadow: none !important;
+  }
+}
 
 .sidebar-mini-md {
   @include media-breakpoint-up(md) {
     @include sidebar-mini-breakpoint;
   }
 }
+@include media-breakpoint-down(sm) {
+  .sidebar-mini-md.sidebar-collapse .main-sidebar {
+    box-shadow: none !important;
+  }
+}
 
 .sidebar-collapse {
   .sidebar-no-expand.main-sidebar.sidebar-focused,

dist/css/adminlte.css

@@ -11288,6 +11288,10 @@ body.sidebar-collapse:not(.sidebar-mini-md):not(.sidebar-mini) .main-header::bef
   }
 }
 
+.sidebar-collapse:not(.sidebar-mini):not(.sidebar-mini-md) .main-sidebar, .sidebar-collapse:not(.sidebar-mini):not(.sidebar-mini-md) .main-sidebar::before {
+  box-shadow: none !important;
+}
+
 .sidebar-collapse .main-sidebar, .sidebar-collapse .main-sidebar::before {
   margin-left: -250px;
 }
@@ -12542,6 +12546,12 @@ body.sidebar-collapse:not(.sidebar-mini-md):not(.sidebar-mini) .main-header::bef
   }
 }
 
+@media (max-width: 991.98px) {
+  .sidebar-mini.sidebar-collapse .main-sidebar {
+    box-shadow: none !important;
+  }
+}
+
 @media (min-width: 768px) {
   .sidebar-mini-md .nav-sidebar,
   .sidebar-mini-md .nav-sidebar > .nav-header,
@@ -12649,6 +12659,12 @@ body.sidebar-collapse:not(.sidebar-mini-md):not(.sidebar-mini) .main-header::bef
   }
 }
 
+@media (max-width: 767.98px) {
+  .sidebar-mini-md.sidebar-collapse .main-sidebar {
+    box-shadow: none !important;
+  }
+}
+
 .sidebar-collapse .sidebar-no-expand.main-sidebar.sidebar-focused,
 .sidebar-collapse .sidebar-no-expand.main-sidebar:hover {
   width: 4.6rem;