Hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>) from the local shop (dilute, 2-3%) sometimes has a stabilizer to slow its breakdown rate and increase its "shelf-life", since we'd like to keep it around the house on our shelf for years, and the shop would like the option to keep it on their shelf for a while as well.

Examples of H<sub>2</sub>O<sub>2</sub> stabilizers include acetanilide and sodium citrate.

[This answer][1] notes that the Soyuz spacecraft (the one with the now-patched hole) also has a "shelf-life" and this one is only about 200 days, for reasons explained there.

Is it known if the Soyuz spacecraft(s) docked to the ISS use chemical stabilizers in its H<sub>2</sub>O<sub>2</sub> so that it can remain docked to the ISS for 200+ days?

(Note that the Soyuz's H<sub>2</sub>O<sub>2</sub> is at a much higher concentration [82%] than what you can buy at your grocery store.)

More info about the situation:

 - [Did NASA “publish”, then “delete” this and other photos of the ISS leak?][4]
 - [August 30th 2018 Soyuz leak, any dangers for re-entry?][3]
 - [How could the 2018-08-30 Soyuz MS-09 / ISS leak be so slow?][2]

[1]: https://space.stackexchange.com/a/31318/12102
[2]: https://space.stackexchange.com/q/30501/12102
[3]: https://space.stackexchange.com/q/30393/12102
[4]: https://space.stackexchange.com/q/30451/12102