IOS Safari 10: TypeError: Module name constructs an invalid URL

Getting this error when using dimport via script tags in Safari 10 on ipad:

```
TypeError: Module name constructs an invalid URL.
```
HTML script tags:
```

```
Debugger is hitting at this line in the transpiled code:
```
return new Function("return import('" + o + "')").call();
```

I've included the dimport scripts as part of my Svelte build and they bootstrap the app itself. Any help would be appreciated!

Reproduce the report in Safari 10 on an iPad using the two HTML script tags and the Svelte-built dimport bootstrap. Start at the transpiled `new Function("return import('" + o + "')").call()` call and trace the module URL it receives. Done means the app bootstraps without the invalid-URL TypeError in this setup.

Written by the indexing model from the issue text.