MediaWiki:Common.css

Note: After publishing, you may have to bypass your browser's cache to see the changes.

• Firefox / Safari: Hold Shift while clicking Reload, or press either Ctrl-F5 or Ctrl-R (⌘-R on a Mac)
• Google Chrome: Press Ctrl-Shift-R (⌘-Shift-R on a Mac)
• Edge: Hold Ctrl while clicking Refresh, or press Ctrl-F5.

# Replace the JAVASCRIPT_CODE section with this updated version:
/* Collapsible portlet styling for Vector (legacy & 2022) */
.mw-custom-collapsible .vector-menu-heading,
.mw-custom-collapsible h3 {
  cursor: pointer;
  user-select: none;
}

/* Arrow icon (left) */
.mw-custom-collapsible .vector-menu-heading::before,
.mw-custom-collapsible h3::before {
  content: "▶";
  display: inline-block;
  margin-right: .35em;
  transition: transform .15s ease;
}

/* Arrow when open */
.mw-custom-collapsible.is-open .vector-menu-heading::before,
.mw-custom-collapsible.is-open h3::before {
  content: "▼";
}

/* Hide/show content area cross-skin */
.mw-custom-collapsible .vector-menu-content,
.mw-custom-collapsible .body { display: none; }
.mw-custom-collapsible.is-open .vector-menu-content,
.mw-custom-collapsible.is-open .body { display: block; }

/* Optional: tidy spacing */
#mw-panel .mw-portlet.mw-custom-collapsible { margin-bottom: .5rem; }