There are breaking changes in the Files frontend API that break the file actions and the file sidebar in this app on NC >= 33.

\### The file actions

This one should be simple to adjust.
See how it's been done in the approval app: https://github.com/nextcloud/approval/pull/350
You need \`@nextcloud/files\` 4.0.0-beta.x (currently beta.9).

\### The file sidebar tab

It's been done in the approval app as well: https://github.com/nextcloud/approval/pull/355
Approval has been migrated to Vue 3, I don't know how different is the custom element stuff in Vue 2.

This is a slightly deeper change. The sidebar tab is now registered as a custom DOM element made out of a Vue component. The component will get the current selected file as a prop. Begin of the insertion

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### Test Steps

1. Start `Nextcloud 33`

2. Enable `integration_openproject` app version `3.0.0-alpha.1`

3. Check:&nbsp;

* Batch action: `Link to work package`

<img class="image_resized op-uc-image op-uc-image_inline" style="width:287px;" src="/api/v3/attachments/918499/content">

* File context menu items: `OpenProject` and `Link to work package`
👉 Check clicking `OpenProject` item opens the sidebar tab

<img class="image_resized op-uc-image op-uc-image_inline" style="width:269px;" src="/api/v3/attachments/918500/content">

* `OpenProject` sidebar tab

<img class="image_resized op-uc-image op-uc-image_inline" style="width:248px;" src="/api/v3/attachments/918501/content">


<br>End of the insertion