regex - Obtain url get variables when htaccess is already creating a query string -

i have rule in .htaccess generates query string according url syntax:

rewriteengine on rewriterule a_([0-9]+)_(.*).html$ article.php?id=$1 [l]

so url this:

a_52_how-to-use-htaccess.html generates: article.php?id=52

my question how allow htaccess add query string other variables sent on url:

a_52_how-to-use-htaccess.html?debug=true

in order have:

article.php?id=52&debug=true

any ideas? thanks.

use qsa flag:

rewriteengine on rewriterule a_([0-9]+)_(.*)\.html$ article.php?id=$1 [l,qsa]

qsa (query string append) flag preserves existing query parameters while adding new one.

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