[Form] Fixed form debugger to work even when no view variables are logged  (e.g. upon redirects)
bug #9394 [Form] Fixed form debugger to work even when no view variables are logged (bschussek)

This PR was merged into the master branch.

Discussion
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[Form] Fixed form debugger to work even when no view variables are logged

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #9331
| License       | MIT
| Doc PR        | -

Commits
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99a4b7e [Form] Fixed form debugger to work even when no view variables are logged  (e.g. upon redirects)