Unused files fills disk after disrupted upload via browser

[aalhitennf]

Steps to reproduce

1. Start uploading file >100mb via web interface
2. Let it upload at least over 10mb
3. Go to another tab (Calendar i.e.), internet connection drops etc.
4. Upload gets cancelled and cannot be continued
5. Unused ~10mb files are left in datafolder/user/upload/web-file-upload-*

Expected behaviour

Unused files should be removed

Actual behaviour

Unused files are filling disk space

Server configuration

Operating system:
Raspbian Stretch Lite
Web server:
Nginx
Database:
Sqlite3
PHP version:
7.0
Nextcloud version: (see Nextcloud admin page)
13.0.5
Updated from an older Nextcloud/ownCloud or fresh install:
Updated from 13.0.*
Where did you install Nextcloud from:
From official site
Signing status:

Signing status

No errors have been found.

[nextcloud-bot]

GitMate.io thinks possibly related issues are #1371 (No file-uploading possible at all), #10711 (Upload Problem on Web Browsers), #3574 (Very slow uploading files), #3667 (Can't upload files from mobile browser), and #9263 (Error when uploading files via web).

[ChristophWurst]

Fixed with #12227