100% this, there's no good reason to do this in JS.
Apache has supported Server Side Includes forever. All you need to do is drop an 'include' in your HTML file and Apache will inject the contents in the right place.
<!--#include virtual="/header.html" -->
I don't know for certain but suspect other webservers will have similar functionality.
Apache has supported Server Side Includes forever. All you need to do is drop an 'include' in your HTML file and Apache will inject the contents in the right place.
I don't know for certain but suspect other webservers will have similar functionality.https://httpd.apache.org/docs/current/howto/ssi.html
Edit:
IIS: https://docs.microsoft.com/en-us/iis/configuration/system.we...
Lighttpd: https://redmine.lighttpd.net/projects/1/wiki/docs_modssi
Nginx: https://nginx.org/en/docs/http/ngx_http_ssi_module.html
Tomcat: https://tomcat.apache.org/tomcat-7.0-doc/ssi-howto.html
Jigsaw: https://www.w3.org/Jigsaw/Doc/User/SSI.html