The Admin Dashboard (OverviewPage) and Admin System (SystemPage) boards each
blanked the whole content pane to a bare headerless lpLoadingBox() on init(),
then rendered the .page-header + panel only once data arrived. So clicking
either tab flashed a full-pane spinner with no indication of which page you'd
landed on, then everything appeared at once.
Extract the page header into a _headerHtml() helper on each page and render it
up front in both the loading state and render(). Now navigating to a board
paints its header (breadcrumb + title + description) instantly and the spinner
is confined to the .admin-panel beneath it — the header stays put and only the
content swaps in when the fetch resolves.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Signed-off-by: librelad <librelad@digitalangels.vip>