This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Lolu chungechunge lwabekwa kunqolobane. Uyacelwa ubuze umbuzo omusha uma udinga usizo.

Thunderbird: How to disable message forwarding in base64

  • 2 uphendule
  • 2 zinale nkinga
  • 1 view
  • Igcine ukuphendulwa ngu Toad-Hall

more options

Apparently since the Update to Thunderbird 45, HTML-mails get forwarded as base64. Is there any way to disable this and go back to the former behavior without downgrading to 38.x?

For example:


User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101

Thunderbird/45.3.0

MIME-Version: 1.0 In-Reply-To: <...> Content-Type: multipart/alternative;

boundary="------------41543626587C7FD8D269B4D8"

This is a multi-part message in MIME format.


41543626587C7FD8D269B4D8

Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit

...Plaintext...


41543626587C7FD8D269B4D8

Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: base64

...HTML and attachements in base 64...


Apparently since the Update to Thunderbird 45, HTML-mails get forwarded as base64. Is there any way to disable this and go back to the former behavior without downgrading to 38.x? For example: -------------- User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.3.0 MIME-Version: 1.0 In-Reply-To: <...> Content-Type: multipart/alternative; boundary="------------41543626587C7FD8D269B4D8" This is a multi-part message in MIME format. --------------41543626587C7FD8D269B4D8 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit ...Plaintext... --------------41543626587C7FD8D269B4D8 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: base64 ...HTML and attachements in base 64... --------------

Isisombululo esikhethiwe

It would seem you located the answer before I got to this query. Thankyou for reporting back with info. could you mark your own response as 'Chosen Solution'.

As additional info, just in case someone else locates this same query. setting "mail.strictly_mime" to true is done via the 'Config editor' located here: 'Menu icon' > 'Options' > 'Options' >'Advanced' > 'General' tab click on 'Config Editor' button.

Funda le mpendulo ngokuhambisana nalesi sihloko 👍 0

All Replies (2)

more options

As it seems, setting "mail.strictly_mime" to true, solves my problem.

more options

Isisombululo Esikhethiwe

It would seem you located the answer before I got to this query. Thankyou for reporting back with info. could you mark your own response as 'Chosen Solution'.

As additional info, just in case someone else locates this same query. setting "mail.strictly_mime" to true is done via the 'Config editor' located here: 'Menu icon' > 'Options' > 'Options' >'Advanced' > 'General' tab click on 'Config Editor' button.