Here's what's fixed in Windows 10 Mobile build 10586.420

Earlier today, Microsoft released Windows 10 build 10586.420 for both PCs and phones. As usual, the PC changelog was easily found, and the list of changes for Mobile was nowhere in sight.

It's an interesting problem that reoccurs every time there's a cumulative update. Microsoft has a Windows 10 Mobile update history page, but it doesn't show a single update on it. This is completely contrary to the Windows 10 for PCs update history site.

The firm finally published a changelog on its Answers forum - once again, rather than the site it created for the purpose of being dedicated to these changelogs. Here's what's new in Windows 10 Mobile build 10586.420:

Reliability, performance and stability improvements.

Improvements to Cortana, including a fix for a problem that sometimes resulted in a crash when performing a search, and corrections to inaccurate times after Daylight Savings Time (DST) on meeting cards and reminders.

Fix for a problem that could result in unexpected battery drain while syncing mail using IMAP.

Improvements to the Maps app, including better stability, improved accuracy, and reduced latency with driving directions.

Improved reliability of syncing text messages from the phone to the cloud.

Reduced amount of time it takes some phones to completely power off after “Goodbye” disappears.

Fix for a problem that caused some phones unable to re-add a primary Microsoft account without resetting after upgrading from Windows Phone 8.1.

Fix for a problem that caused some phones unable to install keyboard and languages without resetting after upgrading from Windows Phone 8.1.

Reduced the number of days a phone can go without restarting to receive an update from 14 days to 7 days.

Fix for a problem that caused the phone to stop ringing from an incoming call, if interrupted by an SMS.

Fix for a problem that caused Project My Screen to stop working on some phones.