The recently published WordPress version 4.7.3 fixes various bugs and six security issues.
Core
WordPress 4.7.3
WordPress 4.7.3 was released on March 6. The new version contains security and bug fixes. You find detailed information about WordPress 4.7.3 in the release post on WordPress.org.
Dev chat from March 8
First meeting topic was the recently released WordPress 4.7.3 and the upcoming version 4.7.4, which will be lead by Pascal Birchler. After that, the core team discussed browser support for the new editor again. The preliminary result is that the majority agree to drop support for older IE versions. The fallback question has to be further discussed — it would also be possible to use a mix like Jeffrey Paul suggested:
»Another option could be a blend of those. Start with including two versions of TinyMCE in core and measure how much the older version is used over the course of, say, 4 months. Then move the current implementation of TinyMCE into a plugin and see how many people install that plugin over the course of, say, 4 months. Then use a simple textarea similar to the one in core now for when JavaScript is disabled as a fallback. We’d only move from one step to the next if the measures in each step are at or below a previously agreed to benchmark.«
Jeffrey Paul in #core Slack channel
The TinyMCE team would also like to drop support for old IE versions.