error:invalid-files

[FrankM]

After update to v1.15.2 i got this error when i try to upload an image. Any tip for me?

2020-11-22T12:19:07.148Z [4567/27041] - error: /api/post/upload
Error: [[error:invalid-files]]
    at validateFiles (/home/nodebb/src/middleware/index.js:106:15)
    at Layer.handle [as handle_request] (/home/nodebb/node_modules/express/lib/router/layer.js:95:5)
    at next (/home/nodebb/node_modules/express/lib/router/route.js:137:13)
    at Form.<anonymous> (/home/nodebb/node_modules/connect-multiparty/index.js:114:7)
    at Form.emit (events.js:315:20)
    at emitCloseNT (internal/streams/destroy.js:87:10)
    at processTicksAndRejections (internal/process/task_queues.js:79:21)
2a02:908:1268:1d50:8ae5:7738:f666:faf3 - - [22/Nov/2020:12:19:07 +0000] "POST /api/post/upload HTTP/1.1" 500 76 "https://URL/topic/889/zweites-fenster" "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:83.0) Gecko/20100101 Firefox/83.0"

[FrankM]

Ok, fixed it.

npm i [email protected]
./nodebb upgrade

But i don't know why!?!?!?