Why does Firefox Dev Tools show transferred bytes as larger than the actual size bytes?

Why does Firefox Developer Tools display a "Transferred" bytes value that is significantly larger than the actual "Size" bytes value, and what factors contribute to this discrepancy?

The discrepancy between the "Transferred" bytes and the "Size" bytes in Firefox Developer Tools occurs because these columns measure different things:

Size: This column shows the size of the resource after decompression (e.g., if the resource is a compressed file, this column shows the size after it has been decompressed).

Transferred: This column shows the actual amount of data transferred over the network, including any overhead such as headers and metadata.

The "Transferred" bytes can be larger than the "Size" bytes because it includes additional network overhead, while the "Size" bytes only account for the actual content size.