I've done something silly, I had an older nRF52-DK loaded with Espruino 2.00 (latest that applies) and was delighted that it seemed to discover/connect faultlessly via the Web-IDE link with a recent Chrome browser on my older Ubuntu 16.04 workstation.
Today I did several experiments changing the bootloader (mBed dap) instance on the board, and then upgrading the bootloader via JlinkEXE 6.5x under Ubuntu 16.04. I did a lot of drag and dropping of several pre-compiled BLE apps, again just experimenting.
After, I tried to go back to my initial condition, that is Jlink driver from the Nordic site, and Espruino v. 2.00 the web-serial connection works OK, but my web-ble does not?! Nordic Connect on my MotoE finds the Espruino-DK ble advertisement, and the uart service will connect.
I get a failure to web-ble pair in one instance, and then it refuses to start at all next time. I can't see what I could have changed visa vie my previous Espruino install???
Any ideas what I've done wrong restoring this cool functionality?