Index: src/mail.rs
==================================================================
--- src/mail.rs	
+++ src/mail.rs	
@@ -7,11 +7,10 @@
 		validate,
 	},
 };
 
 use std::{
-	borrow::Cow,
 	collections::{
 		HashMap,
 		HashSet,
 	},
 	io::Error,
@@ -160,15 +159,11 @@
 				&& let Some(date) = mail.date()
 			{
 				reply.push(format!("<u><i>Date:</i></u> <code>{date}</code>"));
 			}
 			reply.push("</blockquote><pre>".into());
-			//let header_size = reply.join(" ").len();
-			let mut header_size = 0;
-			for i in reply.iter() {
-				header_size += i.len() + 1;
-			}
+			let reply = reply.join("\n");
 
 			let html_parts = mail.html_body_count();
 			let text_parts = mail.text_body_count();
 			let attachments = mail.attachment_count();
 			if html_parts != text_parts {
@@ -176,11 +171,11 @@
 			}
 			//let mut html_num = 0;
 			let mut text_num = 0;
 			let mut file_num = 0;
 			// let's display first html or text part as body
-			let mut body: Cow<'_, str> = "".into();
+			let mut body: String = "".into();
 			/*
 			 * actually I don't wanna parse that html stuff
 			if html_parts > 0 {
 				let text = mail.body_html(0).stack()?;
 				if text.len() < 4096 - header_size {
@@ -189,22 +184,22 @@
 				}
 			};
 			*/
 			if body.is_empty() && text_parts > 0 {
 				let text = mail.body_text(0)
-					.context("Failed to extract text from message")?;
-				// 7:
+					.context("Failed to extract text from message")?
+					.replace("\r\n", "\n");
+				// 6:
+				// - (headers)
 				// - (mail text)
-				// - 1 trailing newline
 				// - 6: </pre>
-				if text.len() < 4096 - ( header_size + 7 ) {
+				if text.len() < 4096 - ( reply.len() + 7 ) {
 					body = text;
 					text_num = 1;
 				}
 			};
-			reply.extend(body.lines().map(|x| x.into()));
-			reply.push("</pre>".into());
+			let msg = format!("{}{}</pre>", reply, validate(&body).stack()?);
 
 			// and let's collect all other attachment parts
 			let mut files_to_send = vec![];
 			/*
 			 * let's just skip html parts for now, they just duplicate text?
@@ -222,11 +217,10 @@
 				files_to_send.push(mail.attachment(file_num.try_into().stack()?)
 					.context("Failed to get file part from message.")?);
 				file_num += 1;
 			}
 
-			let msg = reply.join("\n");
 			for chat in rcpt {
 				if !files_to_send.is_empty() {
 					let mut files = vec![];
 					// let mut first_one = true;
 					for chunk in &files_to_send {

Index: src/main.rs
==================================================================
--- src/main.rs	
+++ src/main.rs	
@@ -3,10 +3,13 @@
 //! available in configuration, everything else is sent to default address.
 
 mod mail;
 mod telegram;
 mod utils;
+
+#[cfg(test)]
+mod tests;
 
 use crate::mail::MailServer;
 
 use async_compat::Compat;
 use just_getopt::{
@@ -50,11 +53,11 @@
 	let parsed = specs.getopt(args);
 	for u in &parsed.unknown {
 		println!("Unknown option: {u}");
 	}
 	if !(parsed.unknown.is_empty()) || parsed.options_first("help").is_some() {
-		println!("SMTP2TG v{}, (C) 2024 - 2025\n\n\
+		println!("SMTP2TG v{}, (C) 2024 - 2026\n\n\
 			\t-h|--help\tDisplay this help\n\
 			\t-c|--config …\tSet configuration file location.",
 			env!("CARGO_PKG_VERSION"));
 		return Ok(());
 	};

Index: src/telegram.rs
==================================================================
--- src/telegram.rs	
+++ src/telegram.rs	
@@ -1,6 +1,9 @@
-use crate::utils::Attachment;
+use crate::utils::{
+	Attachment,
+	validate,
+};
 
 use std::{
 	collections::HashMap,
 	fmt::Debug,
 };
@@ -55,11 +58,11 @@
 		})
 	}
 
 	/// Send message to default user, used for debug/log/info purposes
 	pub async fn debug (&self, msg: &str) -> Result<Message> {
-		self.send(&self.default, format!("<pre>{msg}</pre>")).await
+		self.send(&self.default, format!("<pre>{}</pre>", validate(msg).stack()?)).await
 	}
 
 	/// Get recipient by address
 	pub fn get (&self, name: &str) -> Result<&ChatPeerId> {
 		self.recipients.get(name)

ADDED   src/tests.rs
Index: src/tests.rs
==================================================================
--- /dev/null	
+++ src/tests.rs	
@@ -0,0 +1,22 @@
+use crate::utils::validate;
+
+use stacked_errors::{
+	Result,
+	StackableErr,
+};
+
+#[test]
+fn check_valid () -> Result<()> {
+	let html = "<p>Some <b>valid</b> HTML</p>";
+	let res = validate(html).stack()?;
+	assert_eq!(res, html);
+	Ok(())
+}
+
+#[test]
+#[should_panic = "Found special tag while closing generic tag"]
+fn check_invalid () -> () {
+	let html = "<p>Some <b>valid</b> HTML</p></code><a href='http://somewere.com'>Link injection!</a>";
+	let _ = validate(html).unwrap();
+	()
+}

Index: src/utils.rs
==================================================================
--- src/utils.rs	
+++ src/utils.rs	
@@ -23,9 +23,8 @@
 /// Pass any text here to be validated as HTML, breaks on validation errors
 pub fn validate (text: &str) -> Result<&str> {
 	let fragment = Html::parse_fragment(text);
 	if !fragment.errors.is_empty() {
 		bail!(fragment.errors.join("\n"));
-	} else {
-		Ok(text)
 	}
+	Ok(text)
 }