Should I merge it now? Yes.
The hold on a8be95a5dd is closed.
8dda6fb483 is the only change since the last review. A sections change now forces the data rebuild that the resolve key used to skip. Destroy sets a flag that the loader checks before it starts another import(), and again before it writes the cache.
I would merge 8dda6fb483. The branding cache from 7309f6bd50 is still what stops the appearance tab from importing layouts on every change-detection pass.
What the new commit changes
resolveSectionsOnce, lines 142 to 162
When sections arrive after init, or a color input changed, ngOnChanges calls resolveSectionsOnce(!!changes['sections']). If that flag is true, the key match does not return early. The method still runs the map that copies item.data into resolvedData, then asks the loader for any layout id that is not already cached.
White-label home paints the cached cover page, then refreshPublishedCoverPage replaces coverPageData. The preview builds a new sections array from that payload. The flag is true, so a new headline, image, or section color is copied even when the layout list and page colors are the same. That was the miss on a8be95a5dd.
ngOnDestroy, lines 152 to 156 and the loader, lines 248 to 276
previewDestroyed is set before the generation bump. The loader returns immediately if the component is already gone. A caller that was waiting on the in-flight promise checks the flag again after that wait, so it does not start a second batch. If the import finishes after destroy, the result is not written and markForCheck is not called. PendingTasks.done() still runs.
The idle tab still does not spin
The getter in WlsAppearanceComponent still returns the same branding object while the color, logo, text, font, and background image are unchanged. The appearance parent uses default change detection, and the cover preview is OnPush. A stable input means the preview does not run ngOnChanges, so it does not build a new sections array on an idle pass.
A real palette edit still produces a new branding object. That rebuilds section data and recolors the embed. Layout ids already in layoutComponents are not imported again.
The resolve key still ignores the section payload. It no longer has to carry that payload, because a sections change forces the rebuild on its own. ngOnInit calls resolveSectionsOnce() without the flag. By then the first ngOnChanges has usually stored the key, so init only joins a load that is already going.
What I did not run
I did not open /edit-preference/whitelabel, watch Chrome's task manager, or publish a cover-page copy change against a running white-label home. The rebuild and the destroy guard are the branches in 8dda6fb483.
GitHub reports the pull request open and mergeable. Status checks are still pending. After merge, the useful manual checks are still the ones in the test plan. Idle the cover preview for a minute, change a palette color, and confirm a published section edit shows up on white-label home after the refresh.