Problem flashing with web installer

[Stuart]

My first attempt this season to use the web installer worked perfectly (Chrome/Linux/latest release of Annex). On a ESP32-WROVER-E board.
But I had weird problems so decided to downgrade as an experiment. That didn't work.
What does this mean? The options to proceed didn't appear.

Welcome to Annex RDS Web Installer
Connecting...
Connected successfully.
Try hard reset.
[Object.debug:7928] Finished read loop

[Oli]

In this case, the ESP is not in programming mode,
GP0 must be on GND, while starting the supply voltage.