Use themed favicon-fb

Signed-off-by: Julius Härtl <jus@bitgrid.net>

apps/theming/lib/ThemingDefaults.php

@@ -341,7 +341,7 @@ class ThemingDefaults extends \OC_Defaults {
 		if ($image === 'favicon.ico' && ($customFavicon !== null || $this->imageManager->shouldReplaceIcons())) {
 			$route = $this->urlGenerator->linkToRoute('theming.Icon.getFavicon', ['app' => $app]);
 		}
-		if ($image === 'favicon-touch.png' && ($customFavicon !== null || $this->imageManager->shouldReplaceIcons())) {
+		if (($image === 'favicon-touch.png' || $image === 'favicon-fb.png') && ($customFavicon !== null || $this->imageManager->shouldReplaceIcons())) {
 			$route = $this->urlGenerator->linkToRoute('theming.Icon.getTouchIcon', ['app' => $app]);
 		}
 		if ($image === 'manifest.json') {