#ui 3 articles

• Sharing text through a URL (Teams /share, mailto) breaks at length limitsgotchas / spfx"Send to Teams" (/share?msgText) dies with AADSTS90015 on long answers and mailto silently won't open; cap the URL payload and put the full text on the clipboard
• Your Application Customizer runs again inside SharePoint dialog iframesgotchas / spfxA floating button rendered twice, the copy pinned to the dialog's corner; refuse nested browsing contexts before anything else (+ un-render path and why a body MutationObserver needs a definitive „no“)
• Your Application Customizer's floating UI disappears when navigating the sitegotchas / spfxThe button vanishes as you click around the site; visibilitychange never fires on in-page nav, so re-render on navigatedEvent (+ a MutationObserver backstop that stops re-reading configuration after a definitive…