## Issue
`normalizeUri` | `parseURI` is expensive and has been causing sluggish operations when called repeatedly or within a loop.
## Change
Since I'm not confident enough to remove the call entirely from makeSelectClaimIsMine (although I've yet to find a scenario that the uri is not already normalized), we'll try caching the calls instead.
## Results
- in a simple test of toggling between 2 category pages, we saved 20ms from `parseURI` calls alone.
- in a test of opening all categories one time, the memory usage remained similar. This makes sense since we removed a `makeSelect*` (which creates a selector for each call + not memoizing), and replaced that with a cached selector that's actually memoizing.
## Issue
When comments are refreshed, each `Comment` gets rendered 4-5 times due to reference invalidation for `othersReacts` (the data didn't actually change).
## Change
For selectors without transformation, there is no need to memoize using `createSelector` -- just access it directly. Also, don't do things like `return a[id] || {}` in a reducer, because the reference to the empty object will be different on each call.
Always return directly from the state so that the same reference is returned.
This simple change avoided the wasted resources needed for `createSelector`, and reduced to render to just 2 (initial render, and when reactions are fetched).
- use `selectActiveChannelClaim` as that takes the current channel list into account (i.e. correct state when all channels are deleted).
- `selectActiveChannelId` should probably be removed or not exposed through a selector, as it is not updated when channel list changes?
