User reported: "Stable chrome version 61.0.3163.98 and chrome beta version 62.0.3202.29" Same behavior seen across both. 
OS: Android 8.0 and 7.1.1, phones listed below: 

What steps will reproduce the problem?
(1) Turn on Talkback
(2) Launch Chrome specifically to the NTP (New Tab Page) 
(3) Navigate to the search box 
(4) Double tap on the search edit box

What is the expected result? Keyboard always launches

What happens instead? Keyboard launches intermittently per the device breakdown listed above. On the Note 8 with 7.1.1, Talkback says "End of Field" instead of describing an edit box. This happens across several keyboards including the native gboard and this addon: https://play.google.com/store/apps/details?id=de.bright_side.blind_accessibility_keyboard&hl=en 

Two users report this issue on a variety of phones: 
First user: 
Pixel C running Android 8.0 - cannot reproduce 
Note 8 running Android 7.1.1 - always reproduce on NTP using several different software keyboards, cannot reproduce on edit fields on other pages. She demonstrates all of this in the audio file below.  
Second user: 
Nexus 5X (browser version unknown) - intermittently reproduce 
Moto X First Gen (browser version unknown) - intermittently reproduce  

Audio recording from user: https://drive.google.com/file/d/0B9Jh9xinQN3iUnJhY0pNTFBUZEE/view
Screenshot from a user: https://drive.google.com/file/d/0B9Jh9xinQN3iZDg1UUFKVllEa0k/view 

Full thread with more detail available here: https://groups.google.com/forum/#!topic/eyes-free/APl62x9ZP3o