RewriteEngine On

# 1. Force Global HTTPS Transfer
RewriteCond %{HTTPS} off
RewriteRule ^(.*)$ https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]

# 2. If someone visits /job/any-title, secretly load /job/any-title.html
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{DOCUMENT_ROOT}/job/$1\.html -f
RewriteRule ^job/(.*)$ job/$1.html [NC,L]

# 3. General rule for the rest of your site root files
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME}\.html -f
RewriteRule ^(.*)$ $1.html [NC,L]