: In the address bar, type opera://flags and press Enter. This will take you to the Opera flags page.
The flags page is extensive. To avoid scrolling through hundreds of entries, use the at the top of the page (labeled "Search flags").
In the search bar at the top of the flags page, type "parallel downloading".
When enabled, Opera splits a single file into smaller chunks and downloads them simultaneously (in parallel). Once all chunks are downloaded, the browser reassembles them. This can significantly speed up downloads, especially on fast connections.