Strange behavior ngWig because of css styles

[LoganDupont]

When trying some things out on ngWig i found some strange behaviors caused by the styles.
To reproduce the problems i used this Plunker example

1. If you press backspace in the front of the first paragraph, you will see that it will take the same styles as the header. This is not the case if you try again with some bold/italic text replacing the header. Then the content of the paragraph will still keep it original styles (this is how it should be).
2. When i start from the plunker and try to remove it's content by ctrl+a or selecting everything and then pressing backspace we have different behaviors on the ngWig in the different browsers.

1. Chrome:

• selecting everything or ctrl+a: if we follow the steps in issue 2 you will have still the header styles on your cursor but you can press a second time on the backspace. Only if you press a second time the backspace the styles of the header are removed

2. Firefox:

• selecting everything or ctrl+a: if we follow the steps in issue 2 you will have the header styles that are removed.

3. IE:

• ctrl+a: if we follow the steps in issue 2 you will have the header styles that are removed.
• selecting everything starting from begin to end: bold button will still be activated and can't be deactivated(because of header styles) + can't press second time the backspace to remove the styles
• selecting everything starting from end to start: bold button deactivated (probably because end text is not bold) and you can press second time the backspace to activate the bold button again (also not possible to deactivate the button)

4. Edge:

• ctrl+a: bold button deactivated but if we put focus on inputfield button gets activated and still keeps header styles
• selecting everything starting from begin to end: bold button will still be activated and can't be deactivated(because of header styles) + can't press second time the backspace to remove the styles
• selecting everything starting from end to begin: bold button will still be activated and can't be deactivated(because of header styles) + can't press second time the backspace to remove the styles

Hope you can help me clarifying this strange behavior

Greets,
Logan