can't get browser's context pages after connect_over_cdp

[DeleteXso]

Test on Chrome Version 90.0.4430.212 (Official Build) (64-bit) (Windows 10 20H2 OS Build 19042.928)
chrome lunched with "--remote-debugging-port=9222"

code:

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from playwright.sync_api import sync_playwright
playwright = sync_playwright().start()
chrome = playwright.chromium.connect_over_cdp("http://localhost:9222")
c1 = chrome.contexts[0] # default context
print(c1.pages) # []
print(len(c1.pages)) # 0
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but i am able to get all the opened pages after i open a new_page:

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from playwright.sync_api import sync_playwright
playwright = sync_playwright().start()
chrome = playwright.chromium.connect_over_cdp("http://localhost:9222")
c1 = chrome.contexts[0]
c1.new_page()
print(c1.pages)
print(len(c1.pages)) # 6 (5 opened pages + the new page)
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