Thanks for a bug report. I'm only wondering, is the composer in the Plain text mode, or in the HTML mode?

No probs. Plain text mode.

BTW, one workaround is to create a "New" email and immediately set it to "Preformatted" and then paste the patch into it.

(In reply to Harshula Jayasuriya from comment #0)
> 3. Copy and paste the text into Evolution "Compose Message" window.
> 4. Highlight the text in the "Compose Message" window and set the text to
> "Preformatted"

As you wrote it in the comment #6 to let it work correctly you have to change the format of the block to "Preformatted" before you paste to it. Otherwise the whitespaces will be indeed replaced to non-breaking spaces (as otherwise the spaces would collapse) and when you later switch from "Normal" to "Preformatted" the spaces are not replaced back (as we don't know which spaces were replaced to non-breaking ones - we have to somehow remember that, but it is not that easy).

IIRC, when replying to an email and pasting a patch, there was no way to avoid NBSPs. Do you have a workaround when replying to emails?

(In reply to Harshula Jayasuriya from comment #4)
> IIRC, when replying to an email and pasting a patch, there was no way to
> avoid NBSPs. Do you have a workaround when replying to emails?

No it behaves the same even for the replies (it shares the same code). Please try this (I tried it on 3.20.5):

1) Reply to some plain text mail
2) Go on the first line on the mail, press the Return key, this will create a new block. Make sure that the block is set to "Preformatted"
3) Open gedit and copy&paste the following there:
no space before
 one space before
      more spaces before
<replace this with tabulator>tabulator before
nothing before

4) Copy this and paste it to the block that you've created in step 2
5) Press Ctrl + Shift + i to open the WebKit Inspector
6) Paste the following to the console and compare the expected results

command: document.body.firstChild.innerHTML
expected: "no space before"

command: document.body.firstChild.nextSibling.innerHTML
expected: " one space before"

command: document.body.firstChild.nextSibling.nextSibling.innerHTML
expected: "      more spaces before"

command: document.body.firstChild.nextSibling.nextSibling.nextSibling.innerHTML
expected: "<span class="Apple-tab-span" style="white-space:pre">	</span>tabulator before"

command: document.body.firstChild.nextSibling.nextSibling.nextSibling.nextSibling.innerHTML
expected: "nothing before"

If you would set the block format in step 2 to the "Normal" you would see the following:

command: document.body.firstChild.innerHTML
expected: "no space before"

command: document.body.firstChild.nextSibling.innerHTML
expected: "&nbsp;one space before"

command: document.body.firstChild.nextSibling.nextSibling.innerHTML
expected: "&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;more spaces before"

command: document.body.firstChild.nextSibling.nextSibling.nextSibling.innerHTML
expected: "<span class="Apple-tab-span" style="white-space:pre">	</span>tabulator before"

command: document.body.firstChild.nextSibling.nextSibling.nextSibling.nextSibling.innerHTML
expected: "nothing before"

Does it provide the same output for you?

Hi Tomas, Apologies for the delay, I was on leave.

a) I used some of the steps you suggested and found that I *can* reply to an email and insert preformatted text by doing the following:

1. Create a patch using git format-patch -1
2. Open the patch file in gvim
3. Reply to an email, press enter two times at the top.
4. Set the first empty line to "Preformatted".
5. Copy and paste the text into Evolution "Compose Message" window at the first empty line.
6. Send the email to yourself.
7. Once email is received, "Save as mbox...".
8. Inspect the file with a hex editor.

b) Considering what has been documented in this BZ, perhaps it would be best to *disallow* highlighting existing text and setting it to preformatted until this NBSP issue is resolved? When was substituting spaces with NBSPs introduced into Evolution?

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