Is SPFx still supported by Microsoft?

What type of issue is this?

Question

What SharePoint development model, framework, SDK or API is this about?

💥 SharePoint Framework

Target SharePoint environment

SharePoint Online

What browser(s) / client(s) have you tested

• 💥 Internet Explorer
• 💥 Microsoft Edge
• 💥 Google Chrome
• 💥 FireFox
• 💥 Safari
• mobile (iOS/iPadOS)
• mobile (Android)
• not applicable
• other (enter in the "Additional environment details" area below)

Additional environment details

• browser version 137.0.3296.93
• SPFx version 1.21.1
• Node.js version 22.15.0
• etc

Issue description

I have a fundamental question: Is SPFx still supported by Microsoft?

For the past year, my customers have been constantly experiencing issues with SPFx apps (Teams apps, Command bar Extensions and Form Customizers). Lately, the problems have become so severe that some clients are already considering alternative solutions.
I end up having to explain various workarounds to them, which they are of course not happy with.
The issue with msGraphClientFactory (Issues#10269) is just the cherry on top.

Here is an overview:

Command Bar Extension + SP API Client:

✔️ SharePoint

❌ Teams (MS List App) – Due to CORS, packages from appcatalog/ClientSideAssets/ are not loaded

✔️ MS List

❌ MS List Personal Lists – Extensions occasionally appear, but disappear again after a reload. Due to CORS, packages from appcatalog/ClientSideAssets/ are not loaded

Command Bar Extension + Graph API Client:

✔️ SharePoint

❌ Teams (MS List App) – Due to CORS, packages from appcatalog/ClientSideAssets/ are not loaded

❌ MS List – msGraphClientFactory does not work

❌ MS List Personal Lists – Same as above: extensions sometimes appear, then vanish again after a reload. CORS blocks the packages from loading

Form Extension:

✔️ SharePoint

❌ Teams (MS List App) – Clicking "New Item", "Edit", or "View item" results in no response. However, if you go to More Actions > "Details" > "Edit all", the form opens - Issues#10039

✔️ MS List

✔️ MS List Personal Lists

Now I'm trying to explain to my clients that Command Bar Extensions do not work if the list URL ends with ?env=WebViewList or ?env=WebView. It only works with ?env=Embedded or when the parameter is omitted.

And last week, the Field Customizer was also officially deprecated.
Honestly, I have no desire to deliver this kind of news to my clients in the current situation. Microsoft's decisions are hard to understand.
The fact is: of all the SPFx modules, only web parts are currently working reliably — the rest are deprecated, in a disastrous state, or severely underdeveloped.

These issues are appearing across multiple tenants, ranging from 80 to 2,000 users.

When will these problems be resolved?
Do we need to start preparing for Command Bar Extensions and Form Customizers to be deprecated as well?