Unlike messages file-info, file-info-size and file-info-size-pages, file size is missing in long file descriptions generated by TMH. Compare:
https://commons.wikimedia.org/wiki/File:NDL1875188_%E6%94%AF%E9%82%A3%E5%BB%BA%E7%AF%89%E7%B4%B0%E9%83%A8%E9%9B%86.pdf?uselang=en
10,329 × 6,943 pixels, file size: 198.66 MB, MIME type: application/pdf, 104 pages
WebM audio/video file, VP9/Opus, length 1 h 46 min 44 s, 1,279 × 974 pixels, 2.73 Mbps overall
The file size should be provided in these long descriptions.