htaccess exception for in-page anchor links - regex

Question

I use directives in an .htaccess file to clean-up my website URLs.
For instance, this directive adds a trailing slash:
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_URI} !(\.[a-zA-Z0-9]{1,5}|/)$
RewriteRule (.*)$ /$1/ [R=301,L]
and these remove file extensions:
# hide .php file extensions
RewriteCond %{THE_REQUEST} ^[A-Z]{3,}\s([^.]+)\.php [NC]
RewriteRule ^ %1 [R=301,L]
# redirect .html to /
RewriteCond %{THE_REQUEST} ^[A-Z]{3,}\s([^.]+)\.html [NC]
RewriteRule ^ %1 [R,L]
# redirect .htm to /
RewriteCond %{THE_REQUEST} ^[A-Z]{3,}\s([^.]+)\.htm [NC]
RewriteRule ^ %1 [R,L]
The problem I'm having is with in-page anchors. When I create a link to a section of page, like this:
https://www.mywebsite.com/privacy-policy#information-we-collect
The system outputs this:
https://www.mywebsite.com/privacy-policy/#information-we-collect
How do I adjust the .htaccess file to make an exception for the trailing slash requirement when it comes to in-page anchor links?
A related problem is this:
Although both of these links work:
https://www.mywebsite.com/privacy-policy#information-we-collect
https://www.mywebsite.com/privacy-policy/#information-we-collect
... when they are inside the page (Privacy Policy, in this case).
The URL never adjusts in the address bar to show the fragment identifier (#...). The address bar stays fixed at:
https://www.mywebsite.com/privacy-policy/
When it would normally adjust to:
https://www.mywebsite.com/privacy-policy#information-we-collect
Lastly, while these links with fragment identifiers work within their page, a link with a fragment identifier to another page, does not work.
So, if I'm on the Privacy Policy page, all these links work fine:
https://www.mywebsite.com/privacy-policy#information-we-collect
https://www.mywebsite.com/privacy-policy/#information-we-collect
https://www.mywebsite.com/terms-of-service/
But this is totally unresponsive:
https://www.mywebsite.com/terms-of-service#limitation-of-liability
It only works within the Terms of Service page.

Answer 1

Converting my comments to an answer.
This exception cannot work:
Because a web server (or rewrite rules) don't know anything about anchors because part of URL starting with # is completely handled in browser and is not sent to web server.
#information-we-collect part won't be sent to web server so creating an exception for #... won't really solve the problem. There has to be some other way to create exception e.g. adding a prefix/suffix or a dummy query parameter that rewrite rules can see and take action on.
Alternatively you can handle it on client side itself i.e. inside Javascript code.