Alert: Slow Kit jail setup with copying, cannot bind-mount

[Jammrock]

Describe the bug

I get a "Slow Kit jail setup with copying, cannot bind-mount" warning when opening a document for edit via Collabora.

Steps to reproduce

1. Install OpenCloud via docker compose and enable Collabora.
2. Mount the data dir to the local ext4 file system (OC_DATA_DIR=./app/data).
3. Create and open an ODT, DOCX, or any other file Collabora manages.

Expected behavior

No alerts.

Actual behavior

An alert pops up on the bottom of the page.

Setup

OpenCloud is setup with Docker compose files using the official yml and .env files.

Details

The OS is Ubuntu 24.04.03 LTS. The system is a VM running on Windows Server 2025 Hyper-V. The backing disk in Windows is a stripe-mirror (Windows ReFS) running on U.2 NVMe drives.

OC_DATA_DIR=./app/data

└─sda3                   LVM2_member LVM2 001       1mctz9-HYaZ-UWXt-CA70-yBvS-8LEd-hIntxQ
  └─ubuntu--vg-ubuntu--lv
                         ext4        1.0            7f21b26c-3c77-4ca1-a8c1-b5fe89bbaf10     44.8G    21% /

Additional context

Functionality does not appear affected. I didn't see an Issue opened for this so I created one.

I found this on a Collabora's GitHub repo.

CollaboraOnline/online#13085 (comment)