Here's the quoted changelog, with me emboldening lines which may affect mobile too:
This update includes quality improvements. No new operating system features are being introduced in this update. Key changes include:
- Addressed issue where NTLM fails to generate a challenge response when CredGuard is enabled, NTLMv2 is used, and no target information is provided by the server.
- Addressed issue where Internet Explorer does not respect the “Send all sites not included in the Enterprise Mode Site List to Microsoft Edge” policy when opening favorites.
- Addressed issue in Internet Explorer 11 where a non-administrator user is not able to install an ActiveX control.
- Addressed issue where, after starting Split View, some apps (Microsoft Edge, Hub, Cortana, etc.) no longer receive input when multiple displays are in use.
- Addressed issue with an unnecessary scrollbar in the logon credential provider dialog, which may block use of other fields when the dialog has multiple fields.
- Addressed issue where, during a VM reset, the VM goes into Second Level Paging (SLP) even if there is enough balancer available memory on the host.
- Addressed issue where some non-Unicode fonts (Courier, MS Sans Serif, etc.) do not render characters correctly on non-Latin, single-byte system locales (Greek, Hebrew, Arabic, etc.). Black bars or other artifacts appear instead.
- Addressed issue with an SMS/messaging app that stops working when attempting to delete messages.
- Addressed issue where, after installing the Creators Update, audio output through external decoders no longer works.
- Addressed issue where the IoT shell fails to keep monitored background applications running.
- Addressed issue with high latency when using the Universal Windows Platform (UWP) MIDI API.
- Addressed issue where network printers may fail to install when using the printer vendor’s setup software on machines with less than 4GB of RAM. These printers will install if you install from the Settings app or from Devices and Printer in Control Panel.
- Addressed issue where PrintBRM fails to restore the Print Queue Configurations when printer names are identical and a port is set to FILE:.
- Addressed issue with per user proxy settings not migrating to machine proxy settings.
Good stuff. Available to any phone already on the Creators Update and on the Release Preview ring (see the Reading list below for more!) For the Windows Insider Programme, see inside 'Settings/Update & security'.
See also:
- Phone by phone: WP8/Windows 10 Mobile official upgrade paths
- How to: Get your Lumia 930 or 1520 onto the Creators Update
- How to return your Windows 10 Mobile Insiders phone to 'production' status
- How to upgrade smoothly from Windows Phone 8.1 to Windows 10 Mobile
- How to reset and refresh your Windows 10 Mobile smartphone