need URL to download Kindle app for OSX 10.13.6 High Sierra

https://read.amazon.com/landing

Conclusions, specifically limited to High Sierra:

Brave: ✅

Firefox: ✅

Safari: 🚫

Locally saved Kindle content (not Amazon's Cloud Reader) using the archived reader app: ✅

So it would appear if OP wants to access his or her Kindle purchases, Cloud Reader with Firefox is the way to go.

Update: Peruse these archived versions:

https://web.archive.org/web/*/https://s3.amazonaws.com/kindleformac*

I downloaded and installed the one with the most recent date and it works. At least one older version worked also.

Proceed at your own risk because I happen to know Amazon wants you to use the App Store version.

That's all I can tell you for now.

You should be able to read Amazon purchases using the Kindle Cloud Reader.

https://read.amazon.com/landing

A Kindle device would also be an option, although more expensive.

firstname lastname wrote:

wayback Kindle versions - I downloaded the 30MAY2016 version .dmg and Kindle opens, warning me its an old version.

Try the latest archived version — the one all the way at the bottom of that webpage.

I tried the one you mentioned as well as the newest one, and they both worked fine to read Kindle content loaded on that Mac (more about that later). I did not try any of the others, reasoning that if both the newest and oldest ones work the rest ought to as well.

Having said that... there is a much more plausible explanation your more recently purchased books don't work with older versions of the Kindle app, and I suspect that reason is Amazon's digital rights management. When you "purchase" digital content from anyone, even Apple, it is generally not yours. As in, if you can't sell it, it's not yours. In general we purchase a license to use it (read it, play it... etc) for our own limited personal reasons. Those limitations often include a stipulation that you use the latest version of Kindle (or macOS, or iTunes... etc).

The books I purchased from Amazon long ago still load and work with those old Kindle reader apps... but they are not on the Amazon "cloud". They are stored locally, on the Mac. Whatever may stored on Amazon's (or Apple's) servers can be changed, modified, revoked, etc at their whim for reasons they don't have to explain.

It gets worse because digital content these days — even content that is downloaded and stored locally — can incorporate certificates that expire after some arbitrary period of time, after which they simply won't work either. Same principle applies: You don't own it.

That longwinded explanation may be completely off the rails; I don't know because I have not attempted to load any Kindle content from more recent Amazon purchases. I'm not sure if I even have any.

firstname lastname wrote:

need link / URL to download the Kindle app that runs on OSX 10.13.6 High Sierra.

https://apps.apple.com/us/app/amazon-kindle/id302584613

I believe we are out of luck:

note that attempting reading within Browser on the Amazon site throws an error.

Are you using Safari? Describe the error message. It's working using Safari on this Mac, which also happens to be running OSX 10.13.6 High Sierra.

firstname lastname wrote:

So I need to figure out how to download the stuff from Amazon cloud to my computer. They are data files, why are they not simply clickable to download?

I encourage you to ask on Amazon's digital and device user support forum:

https://www.amazonforum.com/s/topic/0TO4P000000t6ktWAA/kindle-reading-app-windowsmac

Be prepared for a lot of uninformed and probably unhelpful replies though. Their site isn't like this one. No other user support community comes close to Apple Support Communities. ASC is Apple's best kept secret (but they're working on it).

John Galt wrote:

👍

The browser may be a factor, since Safari for High Sierra is becoming increasingly "unsupported".

Ah, good point. I really only use the feature at work if I want to read during lunch and don't have my iPad or Kindle with me. We have reasonably up-to-date Windows computers.

I will make it a point to try both of them later.

I'll be very interested to hear!

👍

The browser may be a factor, since Safari for High Sierra is becoming increasingly "unsupported".

Firefox is slightly less unsupported.

I will make it a point to try both of them later.

Thanks for doing that research!

👍

Fun stuff keeps me motivated.