add_query_arg() removes equal sign from assigned value

[artprojectgroup]

If you add a query array like this:

<?php
$data =[
    'api_id'            => 'xxxxx==',
    'to'                => 123456,
    'text'              => "Prueba",
];
$url    = add_query_arg( $data , 'https://xxx.com' );

The $url you get is this: ​https://xxx.com?api_id=xxxxx=&to=123456&text=Prueba

The line 1142:

<?php
$ret = preg_replace( '#=(&|$)#', '$1', $ret );

Gets "xxxxx==" and return "xxxxx=".

Please fix it.

Kind regards.

[sabernhardt]

The example URL keeps the API ID value intact without the preg_replace, but I don't know what might break (for others) without it.

For history, that line was added in [5999] on ticket #4878.