Echo newline is not visible until refresh

[jcubic]

Issue summary

If there is an echo without newline and then there is echo("\n") the extra newline is not visible.

Expected behavior

It should print two newlines one default and one extra

Actual behavior

it prints a single newline until you resize the page

Steps to reproduce

1. Open CodePen demo
2. Wait until it end printing
3. Resize the page

[jcubic]

Actually, the issue is already fixed in the devel branch.