Can't scroll in safari

### Step 1: Please describe your environment

* ZeroNet version: __0.5.7___
* Operating system: __macOS 10.13.4___
* Web browser: __Safari___
* Tor status: not available/always/disabled
* Opened port: yes/no
* Special configuration: ____

### Step 2: Describe the problem:

#### Steps to reproduce:

1. __Can't scroll in safari, have to use arrow key or space key___
2. _____
3. _____

#### Observed Results:

* What happened? This could be a screenshot, a description, log output (you can send log/debug.log file to hello@zeronet.io if necessary), etc.

#### Expected Results:

* What did you expect to happen?

Start by reproducing the issue in Safari on macOS 10.13.4 using ZeroNet 0.5.7, checking whether pointer or trackpad scrolling fails while arrow and space keys work. Done means normal scrolling works in Safari without regressing the existing keyboard scrolling behavior.

索引モデルが issue の本文から書いたものです。