Generate this string table [duplicate]

Question

For the given string s, generate generate a table like below.

Input:abcd
Output:
abcd
bbcd
cccd
dddd

Input:Hello, world!
Output:
Hello, world!
eello, world!
llllo, world!
llllo, world!
ooooo, world!
,,,,,, world!
       world!
wwwwwwwworld!
ooooooooorld!
rrrrrrrrrrld!
llllllllllld!
dddddddddddd!
!!!!!!!!!!!!!

Trailing whitespace allowed.
This is a code-golf challenge so the shortest solution wins.

Answer 1

APL (Dyalog Unicode), 12 bytes

Anonymous prefix lambda.

{⍵[∘.⌈⍨⍳≢⍵]}

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{…} "dfn"; argument is ⍵

 ⍵[…] index into characters using the array:

  ≢⍵ tally of characters

  ⍳ indices of array of that length

  ∘.⌈⍨ maximum-table using that both going down and across

Answer 2

BQN, 9 bytes^SBCS

Tacit prefix port of my APL answer

⌈⌜˜∘↕∘≠⊸⊏

⌈ maximum-

⌜ table

˜ of self

∘ of

↕ the indices

∘

≠ the string length

⊸⊏ selects characters from that tring

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Answer 3

K (ngn/k), 12 bytes

{x@i|\i:!#x}

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A port of @Adám's APL answer, using a trick with a seeded scan instead of an each-right or each-left.

• i:!#x generate list of indices of the input x, storing in i
• i|\i set up a scan, seeded with i, run over each value in i. this is equivalent to, but one byte shorter, than i|/:i or i|\:i
• x@ index back into the input, implicitly returning

Answer 4

Python 3, 45 bytes

lambda s:[s[l]*l+s[l:]for l in range(len(s))]

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Inputs a string.
Returns a list of strings.

Answer 5

Ruby, 42 bytes

->s{r=0;s.chars.map{|c|s[0,r+=1]=c*r;s.b}}

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