We may have a bug in our sidenav. We need to investigate this issue. As a workaround you can try such solution:

1.Place <nav> element above <mdb-sidenav-layout> like so:

<nav class="navbar">...</nav>
<mdb-sidenav-layout>...</mdb-sidenav-layout>

2.Set sidenav's position to absolute by input <mdb-sidenav #sidenav="mdbSidenav" [position]="'absolute'">

3.Use such styles

html,
body {
  height: 100%;
}

mdb-sidenav-layout {
  position: relative;
  height: 100%;
}

mdb-sidenav-content {
  display: flex;
  height: 100%;
}