Tested with part 1 and part 2 of the test plan.

Perfect logic, but one minor bug is detected.

Page Up does that is written for Page Down in the test plan.
Page Down does that is written for Page Up in the test plan.

All tests passed, but only after line

JS code in the CSV export not detected in both cases - with patch and without patch..

No such notice in the coupi unit. TitleField for coupi unit was not configured.

Added similar fix for the api unit

1. missing system/downloads folder, so can't save file for downloadable product
2. on downloadable product creation "Price" field on the "Files & Pricing" tab is not required, but, if this input is missing, SQL error happens when trying buy this product in front-end.

Notices detected on the E-commerce → Transactions section.

\ImageHelper::ResizeImage - change "thumb_format" of poll's "Image" field to "resize:200x200;default:core/admin_templates/img/ajax_iframe_progress.gif" and try uploading a large (>200 by width/height) file on the poll editing page in the Admin Console

After clean install
Part 4.9 - confirm that you'll see an error message above the system settings list indicating which folders weren't deleted as part of the system setting change. - There appears only "Please manually delete paths:" message. No folder names are present in the message.

2. \NParserCompiler::FindTemplateFiles - recompile all templates from the System Tools section - first convertPathToRelative call is with $path = /core/admin_templates parameter, so no comversion happens - incoming path already is relative. However, result is relative path, so test is passed.

All task-defined coloring is right.

"use the above-created user and products (several with different quantities)"

Without this change - also no SQL error. Maybe, because no MySQL 8.x in the test system.

failed parts 1.10, 1.11. (in both clean install and upgrade cases)

In the D539 added another phrase. Phrase la_fld_ServerHostname is detected as missing during tests.

All by test plan is ok, but missing phrase for "Server Hostname" field (Session log grid column title).

Replaced assertEquels with assertSame in all tests, added in this revision.

Added test case when pounds and ounces both are zero.

Made all requested fixes. Created tests for kUbitFormatter class.

Changed ligic, added unit tests.

Added tests for Core and Custom modules -

Tested all units, additional bugs found in the In-Commerce module.

Partially tested (done testing for Core module part).

1. Languages.

1.1. Broken In-Portal clean install due error in lang prefix, preventing language record creation, required in normal installation process.
1.2. Due specific option_sql configuration for PackName and LocalName fields, possible add only record with values, that already exists. So, when no records in Languages table - can't add first language record.

2. Categories - works well in admin interface, but problematic to add through object, because of Priority field options, that are populated only in OnPreSaveCreated event hook.
3. Change logs - sometimes can't create through object same as languages, due specific Prefix and MasterPrefix field options_sql configuration. But in system records are created by direct SQL, so this not a problem. maybe.
4. Users - can't create and update records with US State, because state options are populated too late - after SetFieldsFromHash already set error to the State field.

I do not understand relation between test plan and proposed automation logic.

Made partial testing. In the u and addr units, on State field Detected unknown_option validation error. As discussed in Zoom, started writing code for automated unit test to check create/update all units with kOptionsFormatter.

Part 3 - "confirm that the Select Module Root Section system setting value was properly saved" - It's not properly saved. After "Save" button pressed, page reloads and returns old Home → Products value.

After clean install:

All test plan passed.

2.2 - this part of test plan is excessive
2.3 - Failed all front-end tests. Always shown Oops, something went wrong text, not 404 page. Always System Log IS created about incident

Boyscout improvements in session.php

Part 2 - "confirm, that you're seeing an Admin Console" - no, adding test code to OnLogin prevents from login to the adm.console.
Part 3 - "replace the tab URL with the provided URL (text after #redirect#)" - seems, missing some action and/or confirmation after this step ot the test plan

Today I have z-index; 0; in DIV Can't provide screenshot without -index today.

Part 2 - all right, so revision is accepted.

done all requested code improvements