missing /tmp/nginx directory let NPM fail

[technicalguru]

• Have you pulled and found the error with jc21/nginx-proxy-manager:latest docker image?
  • No
• Are you sure you're not using someone else's docker image?
  • Yes
• Have you searched for similar issues (both open and closed)?
  • Yes

Describe the bug
Adding a new host or adding a certificate ends with "Internal Error". There is no sign of why this happens. After getting into logs, it appears that NPM fails because of /tmp/nginx is missing and hence, /tmp/nginx/body cannot be created.

It is unclear why the directory disappeared on my installation. It could have been a restart of the VM.

Nginx Proxy Manager Version
2.15.1

To Reproduce
Steps to reproduce the behavior:

1. Remove /tmp/nginx directory
2. Try to create host
3. Click save. "Internal Error" appears

Expected behavior
There should no error and the host shall be created. NPM shall ensure that his directory is available.

Screenshots
N/A

Operating System
LXC VM setup with NPM

Additional context

[jc21]

The /tmp/nginx folder is created upon startup, evidenced here.

With your reproduction steps, would 4. restart the docker container, fix the problem?