Ability to see size on the thumbnail and in list view

[Marco-Sulla]

Checklist

• I made sure that there are no existing issues - open or closed - to which I could contribute my information.
• I made sure that there are no existing discussions - open or closed - to which I could contribute my information.
• I have read the FAQs inside the app (Menu -> About -> FAQs) and my problem isn't listed.
• I have taken the time to fill in all the required details. I understand that the request will be dismissed otherwise.
• This issue contains only one feature request.
• I have read and understood the contribution guidelines.

Feature description

Please add an option to see the file size over the thumbnail, as for file name and video duration. It could be useful if this can be added to list view too.

Why do you want this feature?

Because it's useful, IMHO, and I suppose not so much difficult to add. Maybe boring.

Additional information

I offer myself as volunteer to do a PR. I just need a hand where to code :)