Tmail-web should display text/plain with a fixed-width font

[guimard]

Description

This mail is well displayed by Thunderbird:

To: [email protected]
Subject: Latency for Tmal
MIME-Version: 1.0
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 8bit
Message-Id: <20250110182107.E5FA813FC7C@server>
Date: Fri, 10 Jan 2025 22:21:07 +0400 (+04)
From: root <[email protected]>

---------++-----------------++-----------------|
         ||      Global     ||  Working hours  |
Requests ||-----------------++-----------------|
         ||   LB   | Proxy  ||   LB   | Proxy  |
---------++--------|--------++--------+--------|
   50%   ||  0.04s |  0.07s ||  0.04s |  3.26s |
   80%   ||  0.04s |   3.5s ||  0.05s | 25.03s |
   90%   ||  0.06s | 11.25s ||  4.19s | 35.22s |
   95%   ||  3.01s | 29.18s ||  5.35s |  37.6s |
   98%   ||  5.81s | 37.41s ||  5.88s | 41.08s |
   99%   ||  5.91s | 42.91s ||  5.89s | 62.54s |
---------++--------|--------++--------+--------|
  failed ||   0.7% |   1.0% ||   1.4% |   1.4%

But Tmail display it with standard font: