Documentation for previous versions

Why is it so hard to get the documentation for previous versions? If I need to make changes to code running version 4.6, the only documentation that seems to be available is 6, and, if I look really hard, 5.x (https://docs.dhtmlx.com/suite5.html) sometimes comes up. Why doesn’t the website have links to older versions? Not everyone can upgrade on a regular schedule.

Notification with the link the older suite documentation can be found on the main page of the docs:
https://docs.dhtmlx.com/

As far as I can see, that only brings me back to version 5.X, which I already indicated I had found. Is documentation still available for version 4.6?

There is no documentation for the old versions of the dhtmlxSuite. Only for the actual supported versions: 6.2.3 and 5.2.
For the older versions you may refer to the “What’s new” section:
https://docs.dhtmlx.com/dhx4_whats_new.html