Some web-based custom widgets do not work properly.

### Steps to reproduce

n/a

### Outcome

#### What did you expect?
n/a

#### What happened instead?
In the same 1:1 room (whether encryption is enabled or not), 2 different users add widgets, and the problems are also different:
Command: `/addwidget https://example.com:26054`
This URL is assumed to point to a PsiTransfer instance.

a) If I add a widget via the `/addwidget` command, I use it:
This widget can be opened. If you try to upload a file, the webpage will automatically reload the moment the file is selected, causing the upload process to be reset.

b) If the other party adds a widget through the `/addwidget` command, I use it:
This widget can be opened, but at the same time, a prompt will pop up asking the user whether to continue; if you try to upload a file, the webpage will automatically reload the moment the file is selected, and a prompt will pop up again asking the user whether to continue, resulting in the forced reset of the upload process.

The problems described in the above two situations will occur 100% of the time, and retrying cannot solve it. That is to say, the above problems cause the widget to not work normally.

**Opening the above URL in Safari does not have the above issue.**

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Adding widgets is done on the Element Desktop.
PsiTransfer is a temporary file sharing service, project homepage: https://github.com/psi-4ward/psitransfer

### Your phone model

iPhone 7 Plus

### Operating system version

iOS 15.6.1

### Application version

Element iOS 1.9.17 (TestFlight)

### Homeserver

Synapse 1.75.0

### Will you send logs?

No