Copy and Paste Malfunction When Using Colours

Copying and pasting paragraphs containing coloured words (different than the default) with empty lines between them, makes the paragraph add an empty line within.
Below, the steps to reproduce:

1. Create a new page
2. Copy and paste a text without empty lines (4 lines in this case)
3. Colour more than 2 lines. Example below:
   
4. Save the page and edit it again
5. Insert an empty line after the first paragraph
6. Copy and paste the paragraph above (containing colour characters)
7. Insert other empty line after the second paragraph
8. Copy and paste the paragraph again
9. The last paragraph will contain empty spaces within it: