You need to enable your site to display php errors.

To show those errors, modify your php.ini with this line:

display_errors = on

Still showing a 404. Also with permalinks off. Should i clear cache? If so, where is this option in una?

2.

This is the .htaccess content

Options -MultiViews -Indexes

<IfModule mod_php5.c>
php_flag allow_url_include Off
php_flag register_globals Off
</IfModule>

<IfModule mod_rewrite.c>
RewriteEngine on
RewriteRule ^m/(.*)$ modules/index.php?r=$1 [QSA,L]
RewriteRule ^page/(.*)$ page.php?i=$1 [QSA,L]
RewriteRule ^s/([a-zA-Z0-9_]+)/([a-zA-Z0-9\.]+) storage.php?o=$1&f=$2 [QSA,L]
</IfModule>

AddType image/svg+xml svg

Is this a correct one? I did not change a thing there.

The one from my dolphin looks very different-

The url in the browser shows this for example

/page/persons-home

but this is not found, but when i change the / to .php?i=      like in

/pagephp?i=persons-home

Then it works in the browser. Rewrite is installed. When i make the changes to the rewrite rules, the errors differ.

https://inspireants.com/una/page/persons-home    Does not work

https://inspireants.com/una/page.php?i=persons-home     This works

Hello, Check in your Vhost
Replace AllowOverride None
by
AllowOverride All
I just check this exatly causes the situation you describe above.
Do not forget to restart apache afterwards.

Up: If you do not have this directive in your Vhost, you can also change it more general way instead of doing it for a single site
In case you are on Ubuntu, edit the file /etc/apache2/apache2.conf (here we have an example of /var/www):
<Directory /var/www/>
    Options Indexes FollowSymLinks
    AllowOverride None
    Require all granted
</Directory>
and change it to;
<Directory /var/www/>
    Options Indexes FollowSymLinks
    AllowOverride None
    Require all granted
</Directory>
then,
sudo service apache2 restart

Thanks. But i am on shared hosting. htaccess file is also accessed. I tested it with adding crapp into it and that showed different results. So i suppose that htaccess is correctly read. 

For example, when i do this (deactivate one rule by using #)

RewriteEngine on
RewriteRule ^m/(.*)$ modules/index.php?r=$1 [QSA,L]
# RewriteRule ^page/(.*)$ page.php?i=$1 [QSA,L]
RewriteRule ^s/([a-zA-Z0-9_]+)/([a-zA-Z0-9\.]+) storage.php?o=$1&f=$2 [QSA,L]

then is get this

Multiple Choices

The document name you requested (/una/page/account-profile-switcher) could not be found on this server. However, we found documents with names similar to the one you requested.

Available documents:

• /una/page.php/account-profile-switcher (common basename)

Please consider informing the owner of the referring page about the broken link.

Renamed it in root. Original in subfolder una, but same result..

What could prevent or override the rules? As the htaccess is read, i reall dont have any idea, what could prevent the rules from beeing applied.

Do not have ssh access?

I do have ssh. But i suppose i cant access vhosts. 

You do not have access to /etc/apache2/sites-available/ ?

The use of .htaccess files can be completely disabled by setting the AllowOverride directive to none:
AllowOverride None

So in this case, the changes in .htacces are not effective.

If I am in this configuration, then I have exactly the same problem you see yourself.

So you can not ask your web host to check this for you if you do not have access?