In Joomla 6.1.4, the Menu Title field in com_menus cannot store a literal less-than character (<).
The < character and all text following it are removed when the menu item is saved.
This prevents valid menu titles containing comparison expressions, for example:
Track < 20 km
The saved title becomes:
Track
A greater-than character works correctly:
Track > 20 km

Steps to reproduce

1. Log in to the Joomla administrator interface as a Super User.
2. Go to Menus and create or edit a menu item.
3. Enter the following value in Menu Title:
   Track < 20 km
4. Save the menu item.
5. Reopen the menu item.

Expected result
The title is stored unchanged:
Track < 20 km
The character should be escaped when rendered in HTML, rather than removed when the value is saved.

Actual result
The title is truncated:
Track
The < character and everything following it are removed.
Using the encoded form does not solve the issue:
Track < 20 km
It is decoded and filtered in the same way.
Additional tests
This value is stored correctly:
Track > 20 km
This value is truncated:
Track < 20 km

Environment

• Joomla: 6.1.4
• PHP: 8.3.31
• Database: MariaDB 11.8.6
• User: Super User
• Global Configuration → Text Filters → Super Users: No Filtering
• No third-party extension is involved in saving the menu item.

Technical analysis
The field is defined in:
administrator/components/com_menus/forms/item.xml
as:

The field has no explicit filter attribute. FormField::filter() therefore passes an empty filter type to InputFilter, which falls back to the generic STRING filtering behavior.
The value is altered before ItemModel::save() and before the menu table is bound or stored.
The relevant processing path is:
FormModel::validate()
→ Form::process()
→ Form::filter()
→ FormField::filter()
→ InputFilter::clean()
→ InputFilter::cleanString()
→ InputFilter::cleanTags()
cleanTags() interprets the literal < as the beginning of an unterminated HTML tag and removes the remaining text.

The global text-filter setting is not consulted in this path, so selecting No Filtering for Super Users has no effect.

Why this should be considered a bug
A menu title is plain text and may legitimately contain mathematical or comparison characters.
Input sanitization should prevent HTML injection, but a literal comparison expression such as:

Track < 20 km
should be preserved in storage and safely escaped during HTML output.
The current behavior silently changes user data and makes some legitimate menu titles impossible to create.