Steps to reproduce the issue

Using multiple template styles linked to multiple menu items (e.g. Template Style 1 assigned to 20 menu items, Template Style 2 assigned to a different set of menu items, etc) returns a 404 when clicking a menu item once past a certain number of menu items or templates. Some menus work as they should, some don't

Expected result

Page is displayed correctly with assigned menu style

Actual result

404

System information (as much as possible)

Seems to be a permanent bug across all Joomla versions but. Joomla 5.1.2, php 8.3.7

Additional comments

Hi

I've had this issue over multiple versions of Joomla. Just upgrading an older site to J5 and it's flagged it up again.

I have quite a complex menu structure with 4 main menu items all with their own associated extra menus and individual template styles.

When clicking on main menu items this then displays a secondary menu specific to that main menu and with the specific template style for that entire section. In effect a pseudo set of 4 x websites all inside one with 4 templates styles all loading and presenting their own menus depending on the main menu.

This works well with SEF URLS and URL rewriting turned off, however turning this on throws errors..
.....once past a certain amount of menu items or maybe template styles the website no longer displays the article & template, instead throwing a 404 error and the call stack below.
It seems the template isn't being loaded which then breaks the entire page. (Yes the templates are all assigned correctly to relevant menu items!)

Past fixes here viewtopic.php?t=671239 e.g. in J3 adding $this->route(); to getTemplate() function in "root/libraries/cms/application/site.php" worked for some.

I've temporarily managed to get around this by using the 'Direct Alias' plugin which shortens all the url's but I'd like to see if this is fixable without plugins and using native SEF.

Any suggestions?

Function Location

1 () JROOT/libraries/src/Router/Router.php:155
2 Joomla\CMS\Router\Router->parse() JROOT/libraries/src/Application/SiteApplication.php:754
3 Joomla\CMS\Application\SiteApplication->route() JROOT/libraries/src/Application/SiteApplication.php:244
4 Joomla\CMS\Application\SiteApplication->doExecute() JROOT/libraries/src/Application/CMSApplication.php:306
5 Joomla\CMS\Application\CMSApplication->execute() JROOT/includes/app.php:58
6 require_once() JROOT/index.php:32