Scrolling does not work on some topics with CSS body height set to 100%

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3

No, my plugins are the standard ones:

8f2e4.png888×362 19.3 KB

With the exception of GitHub - moparisthebest/discourse-migratepassword: Support migrated password hashes · GitHub which doesn’t modify any UI.

My modifications are just a few color tweaks in CSS in the admin panel.

edit:
Though I just reverted to no CSS tweaks and that fixed everything :disappointed_relieved:, and I don’t know whether to be worried or glad, because why should CSS ever break javascript? here is the offending CSS if anyone cares:

/* dark gray background in body */
body {
  background-color: #E5E5E8;
  height: 100%; }
html {
  background-color: #E5E5E8;
}

/* lt. gray container around main content area */
#main {
  width: 1110px;
  min-height: 500px;
  background-color: #ffffff;
  margin: 0 auto;
  padding: 0 25px 25px; }
  
/* set fixed container sizes */
div.full-width {
  width: 1110px; }
div.container {
  width: 1110px; }
.admin-content {
  width: 1110px; }
#user-menu {
  width: 1110px; }
.modal-outer-container {
  width: 1110px; }

/* keep reply control left justified */
#reply-control {
  left: 0;
  z-index: 999; }

/* login button color tweak for consistency */
.btn-primary {
  background-image: linear-gradient(to bottom, #00AEEF, #009EDA); }

/* top nav & admin button colors */
.nav-pills li>a:hover { /* inactive button hover (lt. blue) */
  color: #009EDA;
  background-color: #CADCEF;
  border-color: #BDBDBD; }
.nav-pills li.active>a, .nav-pills li>a.active { /* active button static (dk. blue) */
  border-color: #16617d;   
  background-color:#00AEEF;
  background-image: linear-gradient(to bottom, #00AEEF, #009EDA);
  box-shadow:inset 0 1px 0 rgba(255,255,255,0.33); }
.nav-pills li.active>a:hover, .nav-pills li>a.active:hover { /* active button hover (dk. blue) */
  border-color: #16617d;   
  background-color:#00AEEF;
  background-image:linear-gradient(to bottom, #00AEEF, #00B0F0);
  box-shadow:inset 0 1px 0 rgba(255,255,255,0.33),inset 0 -1px 2px rgba(0,0,0,0.2);
  color: white; }

/* side nav button colors (profile pages, etc) */
.nav-stacked li.active a, .nav-stacked li.active a:hover { /* active button static */
  background-color: #CADCEF;
  color: #333; }
.nav-stacked .active .icon-chevron-right, .nav-stacked .active:hover .icon-chevron-right { /* arrow bg */
  color: #333;
  background-color: transparent;
  text-shadow: none; }
.nav-stacked li:hover .icon-chevron-right { /* button arrow hover */
  color: #333; }

/* topic list table styling */
#topic-list tbody tr:nth-child(even) {
  background-color:#F0F0F0; }
#main #topic-list th {
  background-color:#E6E6E6; }