fix: allow native form submission for <form target="_blank"> and <button formtarget="_blank">

[eltigerchino]

fixes #11931

This PR ensures that our client submit event listener allows the browser to make a native form submission to open a new tab if a form or button has the target="_blank" or formtarget="_blank" attribute. This should open the form response in a new tab for both GET and POST submissions.

Afaik the other target values such as _parent and _top should function similarly to _self where we just want to update the current page without refreshing (even if Kit is in an iframe).

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[ghostdevv]

On line 2098 we could change it to use that target variable, I can't make a suggestion on github ui unfortunately

[eltigerchino]

On line 2098 we could change it to use that target variable, I can't make a suggestion on github ui unfortunately

Are you referring to const event_form = /** @type {HTMLFormElement} */ (event.target);? I can't find other references with target

[ghostdevv]

Are you referring to const event_form = /** @type {HTMLFormElement} */ (event.target);? I can't find other references with target

I was talking about this line:

kit/packages/kit/src/runtime/client/client.js

Line 2098 in d79d201

(submitter?.hasAttribute('formaction') && submitter?.formAction) || form.action

[eltigerchino]

Are you referring to const event_form = /** @type {HTMLFormElement} */ (event.target);? I can't find other references with target

I was talking about this line:

kit/packages/kit/src/runtime/client/client.js

Line 2098 in d79d201

(submitter?.hasAttribute('formaction') && submitter?.formAction) || form.action

I’m not sure if that’s right. We need the action property to determine the URL the form is sending the request to while the target property species with frame to open the response in