Formatting Issue about br tag in line

[seong954t]

if line is changed, it is created a
tag but it have a problem.

1. Normally, it isn't problem.

2. if you create a new line inside of two lines, it create a
tag as like in the picture below. also, it isn't problem.

3. but, if you write sentence,
tag is removed at line.

4. also, if you write a sentence after delete a previous written sentence, it is same that

So, I think that
tag should be existed always in that case.

I look forward to your reply. thank you :)

[neilj]

2. if you create a new line inside of two lines

How did you do this? Normally "Enter" would split the paragraph, or insert <br>, not insert a block inside another block.