Thank ntozier
Now that the issue has been identified --- Is there anyway to suppress html tag stripping by HTMLawed?
Thanks!!

I managed to fix this issue by commenting the following line:

includes / class.format.php
$text = Format::safe_html($text, array('spec' => $spec));

I'm not sure if this the best solution but it does the job.
Thanks @ntozier for pointing me in the right direction

@RBGE Agree. Simply converting < into &lt; & > into &gt; takes care of security and content. Since OSTicket uses a ready library HTMLawed, its a default implementation I guess by the library.

A small issue. My solution above only works for HTML emails.
@ntozier Can you suggest what should be tweaked for TEXT emails?
Thanks a ton in advance!!

I scanned the entire class.format.php file but could not locate any function or code which works for text emails. Any pointers are appreciated.
Thanks

Thanks @ramrajone
In the latest version of OSTicket, this code is on line 238.

redactor.insert.html(canned.response, false);

I modified the code as you recommended but it did not help. In my case though, the issue is not with canned responses but with incoming text/plain emails. This issue if really hitting me hard.
It would be really great if someone can suggest a code edit.

Just to recap, commenting the following line helped in fixing this issue with text/html emails.

includes / class.format.php
#$text = Format::safe_html($text, array('spec' => $spec));

But I'm unable to find the code which needs to be modified for text/plain emails.

Thanks in advance!

Thanks @ramrajone but I did not really follow what you are trying to convey
I checked both the links you shared and I agree, HTMLawed is improving security. In my case, since its a specific use case, I need to show content between <>.

My mail server is hosted on Cpanel, I'm trying to see if I can make any changes to the incoming email on-the-fly and convert it from text/plain to text/html. Fortunately, I'm able to bypass the filters for html emails.

Thanks again

Already done that. My code looks like this:
` function sanitize($text, $striptags=false, $spec=false) {

    //balance and neutralize unsafe tags.
    //$text = Format::safe_html($text, array('spec' => $spec));
    //above line commented on 2020-02-05 to avoid stripping of <111111>
    $text = self::localizeInlineImages($text);

    //If requested - strip tags with decoding disabled.
    return $striptags?Format::striptags($text, false):$text;
}`

This is working fine but only for text/html emails.

If I get an email with content-type = text/plain, then the <xxx> is still stripping.

@ramrajone Yes.

Thanks @KevinTheJedi -- it worked.

File: include/class.thread.php

inside the class:
class TextThreadEntryBody extends ThreadEntryBody {
I commented the following code:

function getClean() {
        return Format::htmlchars(Format::html_balance(Format::stripEmptyLines(parent::getClean())));
    }

Hope it helps others looking for a similar solution.

Happy weekend!!

Thanks @KevinTheJedi
I totally agree with you. I'm able to take this risk since we are using OSTicket strictly internally.
Nevertheless, I hope to see the Don't Sanitize..... feature in the future releases.
Thanks for the awesome helpdesk system & superb support!!