[3.3.191120-rc1] - White screen after hiding all assets in portfolio

**Describe the bug**
When all assets in Portfolio are hidden and you click on 'Visual', then you can see a white screen. Reloading the page doesn't help.

**To Reproduce**
1. Go to 'Portfolio' (https://staging.bitshares.org/#/account/your-account)
2. Hide all assets
3. Click on 'Visual'
4. Click on 'Active'
5. See white screen

**Expected behavior**
Don`t see a white screen

**Screenshots**


**Desktop (please complete the following information):**

- OS: Windows 7
- Browser: Chrome 71
- BitShares 3.3.191120-rc1

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- OS: Windows 10
- Browser: Firefox 71
- BitShares 3.3.191120-rc1

**Additional context**
Pull request #2894 didn`t help solve the problem

Start by reproducing the Portfolio flow: hide all assets, select Visual, then Active, and confirm the white screen persists after reload. Trace the Portfolio view and its Visual/Active state transition; done means switching back to Active renders normally when no assets are visible.

Written by the indexing model from the issue text.