Managed to solve this! (and thank you WK for replying to my pm).
Here's my case and my solution; I hope this might someday help someone :
Case: What happened was that I, stupidly, disabled my tablet's google keyboard. This left me with no way to input characters onto various apps.. - I tried to re-enable the keyboard, but the tablet went into a 'spin' sending out various error messages (I may have hit a field that required the keyboard to popup, but no keyboard was available, since I had just disabled it..). Under a slight panic, I forced shutdown via continuous press on the power button. Then, when I turned the tablet back on, I was dumbfounded that it didn't cross my mind I'll need that keyboard in order to input my password !! (tablet is password protected).
- - - My initial hunch was to somehow re-enable the keyboard app over USB via Android Studio - though debug mode on the tablet was not set to on, I had a feeling this might somehow work (along with trying to turn the tablet on in some recovery mode via its hardware external buttons) - - - Searched forums / Dell Support / Google Support = No go (for me), don't have the knowledge (or time) to really delve into it right now.. (I'm positive some can pull this off).
- - - Second idea: use a hardware keyboard OTG USB adapter (would have tried this tomorrow, b u t . . .)
- - - Third thought: Logged onto google play on chrome with the account associated with the tablet --> was able to see all of the apps installed on the various devices attached to the account, also able to *install* apps on these devices through google play on chrome!!!
(very) luckily for me, the tablet was wifi enabled at time of crash, and remained that way throughout boots, re-boots and recovery mode tryouts - -> While the tablet was ON and still locked, waiting for a pword to be input --> I chose to install google keyboard on the tablet (through the play store, on chrome, on my PC) --> sure enough, the little download button on the top right hand corner started blinking ! (it was downloading the google keyboard app and installing it).
--> after it finished, I shut the tablet down, waited a bit, turned it back on --> the keyboard was there, in place !!
A long silly story, I hope this'll help somebody though.
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