rewrite the current page contents dynamically rather than loading entire new
pages from the backend.
One of the problems of working on those applications is that Symfony’s Web Debug
Toolbar remains unchanged with the debug information of the first action
executed when browsing the application.
In order to solve this issue, in Symfony 4.1 we’ve introduced a special
Symfony-Debug-Toolbar-Replace HTTP header. Set its value to
1 to tell
Symfony to replace the web debug toolbar with the new one associated with the
If you want to enable this behavior for just one response, add this to your code:
If you work on a SPA application, it’s better to define an event subscriber
and listen to the
kernel.response event to add that header automatically.
[risorsa: Symfony Blog https://ift.tt/2I412t0 ]