For problems with the app itself, the fastest route is the contact route on the official store listing, where the developer reads feedback and keeps improving the player. Playback bugs, format questions, and feature suggestions belong there, because the developer can see the player code.
For corrections to this guide site, such as a step that no longer matches the official listing, a broken link, or a screenshot that needs updating, use the contact route on this site and describe the page and the step that is wrong. Clear reports get fixed first, because a guide that drifts from the official listing helps nobody.
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