Web Bluetooth Failure

Hi,
I'm facing a strange problem with WebBLE with Chromium running on Kubuntu. The device is visible and can be selected but the IDE does fail to connect to the Bangle v1. The browser log states:
either:

" No Services matching UUID 6e400001-b5a3-f393-e0a9-e50e24dcca9e found in Device.".

or

>>> Connecting to Bangle.js 3f8a
index.js:92938 BT>  Device Name:       Bangle.js 3f8a
index.js:92938 BT>  Device ID:         oyJbQyUewHuu3x2K3MAQUg==
index.js:92938 >>> Connected to BLE
index.js:92938 BT> Connected
index.js:92938 BT> Disconnected (gattserverdisconnected)
index.js:92948 [notify_error] Connection Failed.
(anonymous) @ index.js:92948
error @ index.js:94178
(anonymous) @ index.js:99634
(anonymous) @ index.js:95425
closeSerial @ index.js:96412
btDevice.addEventListener.once @ index.js:96351
index.js:92938 >>> Connection Failed.
index.js:92938 BT> ERROR: NetworkError: GATT Server is disconnected. Cannot retrieve services. (Re)connect first with `device.gatt.connect`.

The app loader logs "NetworkError: Connection failed for unknown reason.
ui.js:86 [error] Device connection failed,".

Has anyone an idea on this?