1. There is a flickering at the bottom of the screen throughout the recording. In fact it is absent from the game itself, one of the rare bugs that sometimes appear when recording a number of old games. The cause has not yet been determined.
Similar issue took a place long before, in the video under number 6 - "Ishidō: The Way of Stones" (1990) and in previous one, number 383 - "Lamentation Sword" (1998).
2. In the videos under numbers 378, 381, 383, 384, you can see a grey sphere in the bottom right corner. Nvidia updated their app to thing called... well... "Nvidia App". By default it turned on statistics indicator, same as if recording is on / off, which I've didn't notice. Starting from 385 it will not appear anymore.
First can be turned off by "Alt+R" combination (there is no separate option for in the menu, it seems). Second by setting "None" in the options - "Alt+Z", then "Settings" - "Heads up display" - "Status Indicators" - "Record".
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