Throughout Star Wars Jedi: Fallen Order, Cal uses a broken lightsaber once belonging to his master, Jaro Tapal. The saber used to be double-bladed but only one blade works at the start of the game. There are ways for players to keep that lightsaber with them in its original state throughout the game, thus keeping the memory of Tapal alive.
There are three places to repair the broken lightsaber: the Dathomir workbench, the Bogano workbench, and the Kashyyyk workbench. Players can skip all three of the workbenches by opting out of the first two, and using the flying glitch to go above and around the third. The Kashyyyk bench is the toughest to skip because Star Wars Jedi: Fallen Order's story will force the player to use it when they get close to it. Quickly tapping the JUMP and FORCE SLOW buttons will enable the flying glitch, allowing players to simply fly past the workbench, leaving them with a broken lightsaber. Despite the game forcing players to repair their lightsaber, if they manage to avoid the final workbench, a brokenlight saber will still display during the next few cutscenes.
Later in the game, Cal's lightsaber is crushed after he receives a vision of his master. Youtuber Cinematic Series Gaming really wanted to hold on to that old single-bladed lightsaber, so they used the flying glitch to get on top of the tomb to try to avoid the cutscene. They made it a fair way through the top of the interior of the tomb before the game's graphics stopped rendering, foiling the effort.
After the lightsaber is crushed, Cal gets a new, double-bladed saber, but if the player manages to avoid repairing the lightsaber up to this point, only a single blade will be used during actual gameplay. A double blade can still be achieved at this point, as the player can still visit any of the three aforementioned workbenches to repair the blade. This is useful because there are some saber tricks and game mechanics that can only be achieved with a double-bladed lightsaber. It is possible to beat Star Wars Jedi: Fallen Order with just one lightsaber blade activated, but players cannot avoid the cutscene that gives them a split saber, so the lightsaber will still look like it has two blades.
So why go to all of the trouble? Skipping the double-bladed saber is a trick speed runners can use to avoid some of the longer cutscenes in Jedi: Fallen Order. It also makes the game slightly harder to play because players have to employ a number of tricks and glitches to make the game work with a single-bladed saber. If it seems like too much work, users can always go back to any of the three lightsaber workbenches in Star Wars Jedi: Fallen Order to upgrade their weapon at any time during the game.
Source: YouTube/Cinematic Series Gaming