Because this is an experimental feature (a "flag"), it is not officially part of the stable release yet. While it is generally safe to use, if you experience any browser instability or crashing, you can return to opera://flags , click the "Reset all" button at the top, and relaunch the browser to revert the changes.
By default, browsers often use a single connection to download a file. Enabling "Parallel Downloading" splits the file into separate packages and downloads them simultaneously, which can significantly increase download speeds, especially for larger files. opera flags enable parallel downloading
Open your Opera browser and type the following address into the address bar (URL bar) and press Enter: Because this is an experimental feature (a "flag"),
: By establishing multiple connections to a server for one file, it can bypass per-connection speed limits. which can significantly increase download speeds