### Steps to reproduce

1. Create a work package

2. Log unit costs to it

3. Delete the work package, either from work package list or work package page

1. From work package list, right click on work package and select "Delete"

2. From work package page, click three dots menu, select "Delete"

4. On "Confirm deletion of work package" dialog, click "Delete" button

5. Because the work package has cost entries attached, the bulk delete page opens asking what to do with the cost entry.

6. Do not select anything and click "Delete" button


### What is the buggy behavior?

* Begin of the insertion~~ErrorEnd of the insertion Begin of the deletion ErrorEnd of the deletion 500 page Begin of the insertiondisplayed~~ The 500 error does not occur anymoreEnd of the insertion Begin of the deletion displayedEnd of the deletion


### What is the expected behavior?

1. No 500 error

2. Redisplay the same page prompting for a choice

3. Disable button if nothing is selected


### Begin of the insertionLogsEnd of the insertion Begin of the deletion  Quick analysis and stack traceEnd of the deletion

Begin of the deletion It tries to redisplay the same page, but fails to interpret the hidden `:back_url` parameter because it is url encoded.

On first display of the page, it uses the referer to set a hidden `back_url` parameter, on submit, it uses the provided `back_url` parameter but this one is url encoded.

```text
=> {controller: "work_packages", action: "index", project_id: "demo-project"}
>> Rails.application.routes.recognize_path('https://qa.openproject-stage.com/projects/my-project/work_packages')
=> {controller: "work_packages", action: "index", project_id: "my-project"}
>> Rails.application.routes.recognize_path('https%3A%2F%2Fqa.openproject-stage.com%2Fprojects%2Fmy-project%2Fwork_packages')
/share/ruby/3.4.7/lib/ruby/gems/3.4.0/gems/irb-1.15.3/lib/irb.rb:415:in 'full_message': No route matches "/https%3A%2F%2Fqa.openproject-stage.com%2Fprojects%2Fmy-project%2Fwork_packages" (ActionController::RoutingError)
```

backtrace:

```text
app/helpers/work_packages_helper.rb:210 WorkPackagesHelper#back_url_is_wp_show?
app/views/work_packages/bulk/destroy.html.erb:32
lib/open_project/form_tag_helper.rb:39 OpenProject::FormTagHelper#styled_form_tag
app/views/work_packages/bulk/destroy.html.erb:31
app/controllers/work_packages/bulk_controller.rb:76 block (2 levels) in WorkPackages::BulkController#destroy
app/controllers/work_packages/bulk_controller.rb:74 WorkPackages::BulkController#destroy
```

End of the deletion AppSignal Begin of the insertionerror (when the 500 error was happening):End of the insertion Begin of the deletion error:End of the deletion https://appsignal.com/openproject-gmbh/sites/674718f1d2a5e4a7cb8b2298/exceptions/incidents/1069/samples/674718f1d2a5e4a7cb8b2298-33377048988927274217635558801

###

### Screenshots and other files

<img class="op-uc-image op-uc-image_inline" src="/api/v3/attachments/861138/content"> Begin of the insertion500 error (does not occur anymore)<imgEnd of the insertion Begin of the deletion <imgEnd of the deletion class="op-uc-image op-uc-image_inline" src="/api/v3/attachments/861141/content">

### Environment information Begin of the deletion

_Please check and fill out the following details to help us identify in what versions and distributions of OpenProject the error occurs_End of the deletion

**OpenProject installation type**

* Hosted cloud edition

* Packaged installation

* What distribution?

* Docker All-in-one container

* Docker-compose installation

* Other (please specify)


**OpenProject version**

16.6.1

**Browser**

* [ ] Chrome
* [x] Firefox
* [ ] Safari
* [ ] Mobile Safari
* [ ] Other (please specify)

**Operating System**

* [ ] Windows
* [x] Mac OS X
* [ ] Mobile iOS
* [ ] Mobile Android
* [ ] Linux (please specify distro)
* [ ] Chrome OS
* [ ] Other (please specify)

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