Old nav deprecation

[myasonik]

So in 7.8 we're shipping a new nav and the old nav is continuing to live behind a toggle in advanced settings.

For how long do we want to support that?

The 3 proposals that I can envision or have heard mutterings of:

1. The new nav is a breaking change so the old nav should live until 8.0
2. The new nav requires an extra click to navigate so the old nav should live until search is available (which will presumably allow for less clicking) (ETA 7.10)
3. The old nav is largely incompatible with the planned stacked header (black on white) so support should end then (ETA 7.10)

2 and 3 will probably come at the same time but I wanted to call them out separately just because their reasoning is a bit different and we don't have a super strict plan around it yet.

[elasticmachine]

Pinging @elastic/kibana-core-ui (Team:Core UI)

[myasonik]

Just because of the technical and design difficulties involved, I'd vote for number 3.

@bmcconaghy @ryankeairns @alexfrancoeur — thoughts?

[ryankeairns]

It's safe to assume there is a more-than-zero amount of hacking that would have to occur in order for the old nav to function properly, which also means there would very likely be some amount of broken tests.

Given that, I would also be in favor or removing support for the old nav whenever the new top header is added. Otherwise, we end up trying to ship this patch work along with the new header bar which smells like trouble.

[bmcconaghy]

Makes sense @ryankeairns . One possible argument to the contrary is that this could be considered a breaking change. Not sure that's what I think, but one could make that argument.

[ryankeairns]

@alexfrancoeur , et al, back when we implemented the new nav in 7.8, we created this issue documenting our desire to remove the legacy left nav once the new header was in. That time has arrived and, as further evidenced by the screenshots below, I believe we should move forward with removing the old nav code. Do you agree?

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As you can see, things have deteriorated and the icon-only situation has worsened. It's also interesting that nobody (afaik) has pointed this out as of yet which tells me it's not being used much, if at all, internally (as one metric). On the contrary, feedback has been overwhelmingly positive for the new navigation design.

[alexfrancoeur]

Welp, we wondered if icon mania could have gotten worse. Now we know 😄 I'm fine with removing when we have search. The only issues I'm aware of that have come up through the community is this Discuss post: https://discuss.elastic.co/t/kibana-left-pan-menu-7-8/237821 and this issue: #69646. Both of which have had minimal feedback.

[bmcconaghy]

Yeah I think the time has come to pull the plug on the old nav. Even if a user prefers that old mode, it's become untenable with the explosion of apps in Kibana, and it's not like we're actively maintaining it any longer.