Why Lightning Experience is freezing (crash, hang, become unresponsive) after reload via F5?

Scenario a) "Regular freeze" ONLY (using Chrome v60.0+)

I turned out that the reason was the way how I was starting LEX...

Because I like to use Aloha (Salesforce Classic) and LEX at the same time, I never used the Menu "My Name" > Switch to Lightning Experience. There are lots of reasons to work in both works in parallel. My way to start LEX was to simply use a link pointing to /one/one.app

What I had then, was kind of a hybrid state: on user level I was still an Aloha user. I just run LEX by link. Now I had several Aloha-tabs running side-by-side with several LEX-tabs. I liked that very much. A REAL switch to LEX causes unwanted jumps of some my opened Aloha-tabs to reload in LEX.

I don't now the exact reasons why, but the crash and freezing does not happen, if I use the standard switch mechanism. I don't like it, but for now that "normal" way to switch the different themes is my "workaround".

Also I have tried to change my link to /one/one.app?source=aloha#/home, but this seems not to help. For now it looks like we really need to be Lightning Users to avoid the freezing. For what I've observed, this behavior is very good to reproduce.

I would highly appreciate it if Salesforce could allow us to use just two different URLs to access and switch between the two experiences dynamically and (more importantly!) to use them in parallel peacefully coexisting in tabs like it worked fine until Winter 18.

As said above there is also at least scenario b) and this is not the only reason for such freezings. If you have similar experiences, let's collect them here. This caused my a lot of headache and I'm sure a list of things to check will help others.

We have had this issue in Chrome for some of our developers. Salesforce has told us that this is an issue with Chrome specifically and the fix for us was to enable caching via Session Settings in Setup:

We previously had this disabled as it was caching our components and causing problems in development, but these issues seem to be resolved now.

Any Scenario: use Chrome <= v59.0 or Mozilla Firefox

Now Known Issue has been created by Salesforce confirming the situation: https://success.salesforce.com/issues_view?id=a1p3A000000mCfPQAU

As stated there this issue is caused by LEX with Chrome v60.0+.

I can confirm, that using Chrome v59.0 (or v57.0) now for a couple of hours not one of these freezing occurred. Also from my colleagues using Firefox I got the indication, that none of such freezing are happening.