Worn out chainring or missing tension This is a follow-up to the question I need to replace a cassette for CS-HG500-10 but want to go XT
Yesterday I replaced the cassette, as well as the chain and the jockey wheels and went for a ride. The problem has not disappeared.
I'm thinking that the chainring is completely worn out, but I'm also starting to think about the tension of the chain.
I'm using the biggest chainring almost all of the time, and was in the bad habit of using it with the biggest sprocket of the cassette, cross-chaining the entire range. I've used this chainring about 7500 km (maybe 3/4 of that distance).
When I use the middle chainring (it has 3 chainrings at the pedal), the problem is pretty much gone.
Here is a YouTube video which I made today, where I'm fully breaking and then putting pressure on the pedal, you can see the chain jump.

                
            
Here are some photos of the chainring:



I have already ordered a replacement, but I wonder if chain tension could also be a factor with this.
Could this problem be removed by increasing the chain tension, or does it look like I generally should increase it after replacing the chainring? How could I do that?

Update: The new chainring arrived today. I took pictures of both and compared them. Here is the result:
I will focus on the chain tension part of the answer, as your big chainring is clearly worn out. However, do note that increasing the derailleur spring tension wouldn’t stop the chain skipping on the worn chainring. Therefore, this answer is mainly for the sake of interest.
By chain tension, I believe you actually mean the tension in the rear derailleur spring. This spring takes up slack in the chain. If your spring tension were too low, the chain could be slack in some or many gears. However, I don’t believe that it’s a setting most users need to manually change, as the factory tension is likely sufficient. From this Park Tools page on overhauling rear derailleurs, Shimano and Campagnolo RDs appear to have one setting for increasing the cage tension from the stock setting. SRAM appear to have one setting higher and one lower. I actually don’t know of any clear reasons you would want to increase the cage tension, but it is possible to do so. I suppose that if you were converting to 1x without a clutch equipped RD, you might consider increasing the cage tension, as discussed in this previous Q&amp;A. (If you do this, you might consider using a chain guide as well.)
Less relevant to you, I recall that Friction Facts, an independent researcher later bought by Ceramicspeed, showed that all else equal, higher cage tension meant slightly more drivetrain friction, although manufacturers objected that the cage tension was necessary to ensure good shifting. I believe that Ceramicspeed’s oversized pulley cages contain at least one position which lowers the cage tension from the stock Shimano or Campagnolo setting. The amount of drivetrain friction at stake is quite small, likely considerably less than 1W.