Users saw a blank window with a white strip across the top for seconds
on launch. Root cause: every part of startup, including session restore,
waited for chrome.html's did-finish-load. That event also waits for the
page's subresources, and the bookmarks bar loads its favicons over
bns:// — a BNS lookup plus a network fetch each — so a slow link held the
whole boot. On top of that, seven hidden overlay renderers, every restored
tab, the BNS index build and three network fetches all started in the
same tick and stalled the main thread ~1 s while the toolbar tried to
paint.
- Continue boot at chrome.html's dom-ready (toolbar scripts have run, IPC
listeners exist) instead of did-finish-load; 8 s fallback timer.
- Window and chrome view get the toolbar's --bg for the active theme so
the pre-paint frame is never white.
- Overlay pages (site info, engine picker, downloads, suggestions,
password fill, link status, approval) load 250 ms after the toolbar or
on first use; the approval modal awaits its page so a dapp request
can't hang.
- Session restore is staggered: active tab first, then one background
tab per 150 ms slotted into its saved strip position. Session file v2
records the active index; v1 arrays still load (active = last, as the
old loop effectively did).
- AddonHost gains api.whenUiReady(); Aegis 0.6.2 defers its heavy
dependency loading (noble precompute, bitcoinjs, libauth, WizardConnect)
behind it.
- BNS snapshot warm-up still starts right after createWindow (bookmark
favicons need it); Sia refresh, update check and home-card fetch move
to the post-paint phase.
Measured on a clone of the real profile with nine restored tabs: toolbar
usable at ~0.7 s instead of ~1.5 s, main-thread stall during toolbar load
down from ~1.1 s to ~0.2 s.