For the second time this year the Kindle Fixed Layout Functionality Chart has been updated due to changes in the various Kindle reading systems. I've just completed another round of testing to determine how the latest system updates have affected functionality in fixed layouts, and some of those changes are significant, whether for good or ill.
I've also added a Change Log just above the chart to make it easier to see what's happened since the last updates, as well as adding a row denoting the latest OS version tested for each device or app.
These tests involve loading a minimum of nine different Kindle test files (more if some new variable needs testing) - each of which contain over a dozen pages that have been created specifically for this purpose - onto the seven different Kindle apps and devices I currently own. This creates a series of 72 iterations of a Kindle fixed layout file on a Kindle reading system, requiring a total of 1044 page loads (if each page is only viewed once on each system), and countless orientation changes of each device (which for the Paperwhite is a pain, to say the least), each page of which must be run through a battery of tests to determine what is working and what is not, pursuant to the ten items listed on the chart (only 8 of which I now test), and carefully noting any anomalies that occur. This tends to get somewhat confusing if one is not quite awake, and thus requires a lot of coffee (donations gratefully accepted).
The primary variables involved are the three "book-type" values (comic, children, or none), and the inclusion or absence of region magnification code in a given file. In addition, the orientation-lock variables have generally been included in the testing, with respect to page-spread functionality, which in any case has made no difference, but still has to be tested to determine that this is still true. This, of course, as with the book-type, requires a change in the metadata value, and thus the creation and conversion of a separate Kindle file for just that instance (delineated by titles such as Kindle-FXL-Comic-NoRegMag-Landscape.mobi). Region Magnification itself is dependent on its inclusion or absence within the publication itself rather than the metadata value entered, which is entirely irrelevant.
As mentioned in the notes, and obvious by the data included, I am still only testing these seven Kindle reading systems, due to lack of resources to procure more, or time to deal with it in any event. I plan eventually to get at least one HDX device, but at present just can't justify the investment, not only due to the financial expense, but as much because it frustrates me to no end how poorly the software is designed, and I'd almost rather not know what features are unsupported - or flat out broken - on yet another version of the Kindle OS. If just one feature worked the same on all devices it would make things so much easier.
UPDATE: The 'layout-blank' property has now been tested thoroughly, and the results noted.