I can confirm that Ctrl + DOT unlocks the image in Ubuntu. Then by loading the latest Zinc packages and evaluating "Smalltalk recompile" the issue is fixed.

Many many thanks for your time and for pointing me in the right direction.

On Friday, February 9, 2018, 1:16:15 PM GMT-3, Sven Van Caekenberghe <sven@stfx.eu> wrote:

> On 9 Feb 2018, at 15:06, Sven Van Caekenberghe <sven@stfx.eu> wrote:
>
> It seems the latest Zinc (as loaded by Seaside) does not yet contain this class.
>
> I'll check and come back.

To fix this, for now, you can load the latest ConfigurationOfZincHTTPComponents and do

ConfigurationOfZincHTTPComponents project bleedingEdge load.

After which you have to do

Smalltalk recompile.

And save. You should now be able to restart and your image should come up normally.

If CI builds succeed for older versions of Pharo, I will promote this version to #stable.

Sven