I had to use:

replace \n^\s*\n with \n

The https://github.com/NicholasBuse/sublime_DeleteBlankLines plugin did nothing at all.

Sublime Text 2 & 3

The Comments of @crates work for me,

Step 1: Simply press on ctrl+H

Step 2: press on RegEX key

Step 3: write this in the Find: ^[\s]*?[\n\r]+

Step 4: replace all

Their is a more easily way to do that without regex. you have just to select the whole text. then go to: Edit--> Permute Lines --> Unique.

That's all. and all blank lines will be deleted.

There is a wonderful package (for Sublime 2 & 3) called 'Trimmer' which deletes empty lines. It also does many other useful things.

Refer this: https://packagecontrol.io/packages/Trimmer

Another way, you can use the command line cc.dbl of ConyEdit (a plugin) to delete blank lines or empty lines.

To find extra spaces and blank lines press Ctrl+Shift+F Select Regular Expressions Find

[\n\r]{2,}

and then replace with

\n

to remove all kind of spaces in sublime and dreamviewr

Using find / replace, try pasting a selection starting at the end of the line above the blank line and ends at the beginning of the line after the blank. This works for a single blank line. You can repeat the process for multiple blank lines as well. CTRL-H, put your selection in the find box and put a single newline in the replace box via copy/paste or other method.

In my case some empty lines contained the unicode character zero width space (U+200b). To rid empty lines, including the ones with this unicode character:

\s\x{200b}|^\s