Affects Version/s: 1.14.4, 19w34a, 19w35a, 19w36a, 19w37a, 19w38b, 19w41a, 19w42a, 1.15 Pre-release 1
Fix Version/s: None
Environment:OS: Windows 10 1809
Java: Java 8 Update 191
How to reproduce
1) Put yourself in /gamemode creative.
2) Hold a sword in your hand. (which prevents you from breaking blocks)
3) Hit a block whilst moving. When flying fast and holding down left click it's very noticeable that your movement is getting frozen.
This likely has to do with the fix for https://bugs.mojang.com/browse/MC-156013 freezing players, but when the block breaking is cancelled on the server side the client is not notified correctly.
1) Go on a server with spawn-protection enabled.
2) Break a block in the spawn protected region whilst not an operator. You shouldn't be able to break any blocks.
3) (optional) Put yourself in /gamemode creative. (makes the issue clearer)
4) Start walking whilst attempting to break blocks around you, you'll notice movement keeps getting frozen.