Does a slot swap cause an application to restart when using deployment slot settings? My web application in Azure has two deployment slots - staging and production.
The purpose of the application is to draw a shape. The version currently deployed to the production slot draws a square. The version deployed to the staging slot draws a circle.
Both versions of the application have an application setting called Colour which controls the colour of the shape. Importantly, this is a deployment slot setting - see the example capture below:

The value of this setting is blue in the staging slot and green in the production slot.
When I view the application in the staging slot, a blue circle is drawn. When I view the application in the production slot, a green square is drawn.
When I perform a slot swap from staging into production and view the application in the production slot, a green circle is drawn.
I am struggling to get my head around this. A big advantage of swapping deployment slots is that I am able to swap my pre-warmed staging code into the production slot and prevent users from suffering from downtime or cold-start performance issues. However, by swapping the staging application into the production slot which has different values in the deployment slot setting, haven't I made changes to the application configuration which will trigger a restart? If I was to modify web.config manually or update the deployment slot setting in Azure, the application in the slot would restart. How is slot swapping getting around this?
if both are running 'warmed up' and in 'Always On' mode then the swap would not cause a restart of any kind. But go to this URL and read the point #1 and if any of these things are done then it will restart.
https://docs.microsoft.com/en-us/azure/app-service/deploy-staging-slots#what-happens-during-a-swap