Unintuitive search/filter on `size` and `last_modified` columns

[vidartf]

Both of these columns are non-text type fields rendered to text, and the search/filtering is directly on the non-text value. I.e. for the size column, only exact byte-size numeric values give a hit. For the last_modified columns, it seems (?) to give a hit on any value that has a specific substring of digits in its Unix epoch timestamp.

Ideally, both the columns would have a more clever UX, and would work less as a direct match but instead e.g. as a "greater than / less than" filter.