# If you'd like to omit non-matching lines from the result; add ';d' to the end of the expression.
sed -E 's/<(?:[^<>]*?\salt="([^"]*)")?[^<>]*>/$1/gm;t' <<< "<p>test emoji <span title=\"Smile\" class=\"animated-emoticon-20-smile\"><img title=\"Smile\" alt=\"🙂\"></span> and more <span title=\"Emo\" class=\"animated-emoticon-20-emo\"><img title=\"Emo\" alt=\"😑\" target=\"_blank\"></span><span title=\"Star eyes\" class=\"animated-emoticon-20-stareyes\"><img title=\"Star eyes\" alt=\"🤩\"></span></p>"
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for SED, please visit: https://www.gnu.org/software/sed/manual/html_node/The-_0022s_0022-Command.html