GUI Layout Toolbox

* Fixed "cannot drag flex containers in MATLAB Online"

* Added uix.BoxPanel property MinimizedHeight to return minimized height (title plus border)
* Fixed issue creating layouts prior to R2019b due to modern syntax used in uix.mixin.Container

* Completed support for JavaScript graphics system, from R2022a
* Added support for figure themes, from R2025a
* Removed decorations on draggable dividers
* Reimplemented TabPanel using uitab
* Updated BoxPanel, ScrollingPanel
* Updated documentation

Reverted changes from version 2.3.8, as these introduced issues with the appearance of dividers and tabs

Improved appearance of dividers and tabs in web graphics

Added web graphics support for uix.BoxPanel

* Added details of web graphics support

* Updated for compatibility with R2020b uipanels
* Fixed G1959226 "Scrolling panel scrollbars and blanking plate do not match background color"
* Fixed G1959228 "Scrolling panel sliders remain after child is deleted"

* Fixed G1910801 "Scrolling panel does not work in figure with Units other than 'pixels'"
* Fixed G1911845 "Unexpected reordering of contents as axes toolbar causes axes to be removed and readded"

* Updated for compatibility with R2018b axes toolbars
* Fixed G1804440 "Flex containers position axes incorrectly when ActivePositionProperty is outerposition"

* Set tooltip strings for BoxPanel dock/undock, minimize/maximize, help and close buttons
* Set default padding for flex containers to 5 so that dividers are visible
* Fixed G1358897 "BoxPanel title is truncated on Mac high DPI display"

* Specify minimum width and height of contents in uix.ScrollingPanel
* Update contents position while dragging uix.ScrollingPanel scrollbox
* Scroll uix.ScrollingPanel using mouse wheel

* Added scrolling panel
* Expand and collapse box panel by clicking on title
* Fixed G1493103 "Error on construction behavior is inconstistent with builtin objects"

* Fixed G1175938 "Cannot use data cursor mode with GUI Layout Toolbox containers"
* Fixed G1367337 "Update flex container pointer on mouse press event"
* Fixed G1380756 "Space behind TabPanel tabs should match parent color"

Bug fixes

* Improved box panel title bar appearance
* Changed selection behavior of uix.TabGroup to match that of uitabgroup when the selected tab is removed
* Bug fixes (see release notes)

Bug fixes

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